Performance, Durability, and Service Life of Low Pressure ... · Performance, Durability, and...

232
Volume 1: Technical Report and Results Final Report on Performance, Durability, and Service Life of Low Pressure Propane Vapor Regulators Docket 11073 by Stephanie Flamberg, Matt Goshe, Rodney Osborne, and Steve Speakman Battelle Applied Energy Systems To Propane Education & Research Council 1140 Connecticut Ave. NW, Suite 1075 Washington, DC 20036 September 2006

Transcript of Performance, Durability, and Service Life of Low Pressure ... · Performance, Durability, and...

Page 1: Performance, Durability, and Service Life of Low Pressure ... · Performance, Durability, and Service Life of vii September 2006 Low Pressure Propane Vapor Regulators Battelle Of

Volume 1: Technical Report and Results

Final Report on

Performance, Durability,

and Service Life of

Low Pressure Propane

Vapor Regulators Docket 11073

by

Stephanie Flamberg, Matt Goshe,

Rodney Osborne, and Steve Speakman

Battelle Applied Energy Systems

To

Propane Education

& Research Council

1140 Connecticut Ave. NW, Suite 1075

Washington, DC 20036

September 2006

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FINAL REPORT

on

PERFORMANCE, DURABILITY, AND SERVICE LIFE OF LOW PRESSURE PROPANE VAPOR REGULATORS

Docket 11073

VOLUME 1 – TECHNICAL REPORT AND RESULTS

to

Propane Education & Research Council 1140 Connecticut Ave. NW, Suite 1075

Washington, DC 20036

September 2006

by

Stephanie Flamberg Matt Goshe

Rodney Osborne Steve Speakman

Battelle Applied Energy Systems 505 King Avenue

Columbus, Ohio 43201-2693

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Notice Battelle does not engage in research for advertising, sales promotion, or endorsement of our clients' interests including raising investment capital or recommending investments decisions, or other publicity purposes, or for any use in litigation. Battelle endeavors at all times to produce work of the highest quality, consistent with our contract commitments. However, because of the research and/or experimental nature of this work the client undertakes the sole responsibility for the consequence of any use or misuse of, or inability to use, any information, apparatus, process or result obtained from Battelle, and Battelle, its employees, officers, or Directors have no legal liability for the accuracy, adequacy, or efficacy thereof.

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Performance, Durability, and Service Life of iii September 2006 Low Pressure Propane Vapor Regulators Battelle

ACKNOWLEDGMENTS The authors wish to express their appreciation to the individuals and organizations who contributed to the successful completion of this challenging program. The authors sincerely appreciate the support in time, materials, and shipping expenses for those propane marketers and National Propane Gas Association members that supplied regulators for this testing program and the efforts of the Propane Education & Research Council and NPGA to assist with the collection of the regulator samples for testing. In addition, we would also like to thank the regulator manufacturers and industry experts that provided feedback on the regulator test protocol. This project would not have been a success without their assistance. The authors also wish to acknowledge the program advice and guidance provided by Larry Osgood of Consulting Solutions on behalf of PERC. Larry imparted into the program the practical propane industry experience very necessary in this type of project.

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Performance, Durability, and Service Life of v September 2006 Low Pressure Propane Vapor Regulators Battelle

EXECUTIVE SUMMARY Anecdotal evidence suggests that the natural gas industry effectively and safely uses low pressure regulators in field service for time periods exceeding 30 years. Yet in the propane industry, regulator manufacturers provide regulators that have limited field evaluation capability and regularly carry a 15-year replacement recommendation. To gain a clear understanding of the issues and concerns, the Propane Education & Research Council (PERC) obtained the assistance of Battelle to test a suite of propane vapor regulators that have been recently removed from service and to develop a database on their performance. Regulators considered for this study were standard non-adjusting residential and commercial vapor regulators. Regulators intended for industrial applications, “pounds-to-pounds” regulation, and those intended to be adjusted on a regular basis were excluded from this study. This report summarizes the results of a program conducted by Battelle in which propane vapor regulators, in use from 1 to more than 50 years, were collected from across the country and subjected to a series of tests to determine their performance. Over seven hundred first-stage, second-stage, single-stage, and integral two-stage (includes twin stage and combo) regulators were collected from 27 different states, representing four climate regions. The collection included regulators from different manufacturers, different types of regulators, various service conditions, ages, and environmental conditions. The collection effort specifically targeted first-stage, second-stage, and integral two-stage regulators to examine the assumptions behind the 15-year replacement recommendations. A sampling of single-stage regulators was also tested; however, since the 1995 edition of NFPA 58, the LP-Gas Code, these regulators have not been permitted to be placed into new service and therefore the testing efforts did not focus on their performance. As part of this project, the Gas Technology Institute performed a literature review to determine if there was scientific or engineering support for a 15-year replacement recommendation.

The literature review was not able to document scientific or engineering support for a service-life recommendation of 15-years. The findings of the literature review suggest further research in the use and variability of plasticizers and extenders in the rubber composition of propane regulator components; the long-term effect a propane operating environment has on elastomer and spring performance; and the effect of propane contaminants and off-specification gas on propane regulator performance. A technical paper studying regulators in Korea1 showed that in general the safety devices of the low pressure regulators deviated from “normal operation” (not defined by the authors) after a year of service and deviated from the factory-set discharge start and reset pressures of the new regulators. Overall, the operating and closing pressures also deviated from the pressure range of the new regulators after a year of service. A six year service life was then recommended. Testing of diaphragms from the propane regulators in the field found a loss of tensile strength and

1 Jeong-Rock Kwon, Young-Gyu Kim Gas Safety R&D Center, Korea Gas Safety Corporation, “Aging Characteristics of Low Pressure LPG Regulators for Domestic Use”, May 1999.

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decreased range of motion after five years of service. Researchers suspect a hardening of the diaphragms due to leaching of plasticizers from rubber materials over time. The authors called for further research to improve diaphragm durability and reliability, to investigate the effect of plasticizer extraction from rubber materials on diaphragm performance, and the development of new rubber materials with improved rubber characteristics and properties. Testing of propane regulator springs from the field found a loss in tensile strength after a seven-year service life. The authors called for spring research on the length of the freedom field of the spring, the surface treatment on the ending parts of the spring, quality control in the manufacturing, and reinforcement of durability characteristics. It should be noted that none of the regulators tested were from U.S. manufacturers. However, the Korean study does raise the issue of the long-term effects a propane operating environment has on elastomer and spring performance. Additionally, a review of elastomers reference literature, “The Vanderbilt Rubber Handbook –13th Edition,”2 and “Rosato’s Plastics Encyclopedia and Dictionary,”3 found that additives, particularly plasticizers and extenders, can leach out over time, resulting in physical changes in size, elongation, and tear strength. In regulators, elastomers are used in valve seat discs and diaphragms. Further research is suggested to assess the use and variability of plasticizers and extenders in the rubber composition of propane regulator components. In “Investigation of Portable or Handheld Devices for Detecting Contaminants,”4 findings indicate that while propane for domestic use typically meets commercial grade specifications, contamination occurs in small quantities in the supply chain over time. Further, the impact of propane contaminants and off-specification gas is not well documented. Research is suggested to investigate the effect of propane contaminants and off-specification gas on U.S. propane regulator performance. To test the performance of the low pressure propane vapor regulators, Battelle adapted selected test procedures from the Underwriters Laboratory 144 Standard for Safety for LP-Gas Regulators. UL 144 is intended to establish the initial operating parameters of newly-manufactured regulators, as well as other performance specifications. The test procedures adapted for use were the Flow/Lock-up Tests (Section 21, Section 22, and Section 25.4) and Pressure Relief/Relief Capacity Tests (Section 23 and Section 24). According to this standard, first-stage regulators were expected to lock-up at pressures lower than 130% (for 100 psi and 25 psi inlet pressures) and 150% (for 250 psi inlet pressure) of the outlet set pressure. Second-stage, integral two-stage, and single-stage regulators were expected to lock-up at pressures lower than 120% (for 10 psi and 5 psi inlet pressures) and 160% (for 15 psi inlet pressure) of the outlet set pressure. The pressure relief devices were expected to start-to-discharge at a pressure between 140% and 250% of the outlet pressure for first-stage regulators and 170% to 300% of the outlet pressure for second-stage, single-stage, and integral two-stage regulators. In addition, the relief device was expected to reseat at a pressure greater than 140% of the outlet pressure for first-stage regulators and greater than 170% of the outlet pressure for second-stage, single-stage, and integral two-stage regulators.

2 Ohm, Robert F., “The Vanderbilt Rubber Handbook -13th Edition”, R.T. Vanderbilt Company, Inc., 1990. 3 Rosato, Dominick V., “Rosato’s Plastics Encyclopedia and Dictionary”, Oxford University Press, 1993. 4 Southwest Research Institute, “Investigation of Portable or Handheld Devices for Detecting Contaminants in LPG, Docket 11296”, for the Propane Education and Research Council, Washington, D.C., 2005.

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Of the over seven hundred regulators collected, a subset of 266 regulators was selected for testing based on statistical sampling methods. The 266 regulators were then subjected to external and internal inspections to identify any significant corrosion, damage, or missing components; lock-up testing at three different inlet pressures and four different flowrates; and pressure relief testing. A database of the test results was compiled and is provided in Volume 2. Included within the database are measurements of initial and adjusted outlet pressures; pressure-adjusting screw height before and after adjustment; outlet pressures during lock-up testing; start-to-discharge, reseat pressures, and flow rate during the pressure relief testing; and any leaks or other issues identified during testing. This has resulted in a comprehensive database that allows direct and detailed comparison of regulator performance. The reason for regulator removal was not used as a selection criterion. However, 45 of the regulators had been labeled as “faulty” or “leaking through” by the submitters. Fifty-four tested regulators did not have the reason for removal identified by the submitters. Age appears to have little effect on the performance of first-stage regulators, and only a slight effect on the performance of second-stage regulators. On the other hand, age appears to have a significant effect on the performance of single-stage regulators. Aside from the mechanical differences that provide the pressure control ranges of the three main types (first, second, and single-stage), these types have several components in common – flexible, elastomeric diaphragm, elastomeric seat disc, steel springs, and mechanical linkage. Degradation of the elastomers would affect all types of regulators. The single-stage unit must control over a much wider range of inlet pressures. This wide pressure-control requirement may make the single-stage units more susceptible to elastomer degradation and any corrosion on the metallic linkage parts. Figure ES-1 shows the percentage of regulators that failed to meet the test criteria. As can be seen, these failure rates do not increase with statistical significance. This figure shows a large failure percentage for the age group of 55 to 60 years, however the sample set for this age group was one unit. A caution must be made about the failure rates presented in this report:

The rates presented here should not be construed as projected field failure rates. There are tens of millions of low pressure propane vapor regulators in the field, and failure rates of even ten percent would result in millions of failed units – this is clearly not the case. Rather, these failure rates are the result of an extremely rigorous test protocol that stresses the regulators to conditions not seen frequently in the field. Indeed, the particular combination of tests that were prescribed in the protocol may never be experienced in the field. The intent of the newly-developed testing criteria was to generate failures. These failure rates could then be compared between independent parameters of manufacturer, environment, and others. As shown in Figure ES-1, the rates are indeed significant. If the test were more representative of actual field conditions, several age groups would have had no failures, and others may have had only one failure. One could not compare these low failure rates.

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The key observation here is that the currently used two-stage regulator systems show no significant degradation during the 20 to 25 year period of service that is now standard.

0/20/0

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now

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% o

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ens

% Failed in Group

Figure ES-1. Regulator failures by age.

As previously mentioned, the numbers of regulators tested were fairly evenly distributed between two manufacturers, “A” and “B”, with over 125 of each manufacturer’s units tested. Figure ES-2 shows a summary of the failed regulators. Roughly 53 percent of the regulators tested were from Manufacturer A and approximately 47 percent were from Manufacturer B. Each of these showed similar range of results for lock-up, start-to-discharge, and reseat pressures. While more of the Manufacturer A regulators met the test criteria, this difference is fairly small. These test data were replotted from the perspective of the four environmental regions:

- Warm; dry ( > 53°F; < 73% humidity), - Warm; damp ( > 53°F; > 73% humidity), - Cool; dry (< 53°F; < 73% humidity), and - Cool; damp (< 53°F; > 73% humidity).

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43 out of 145

49 out of 129

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% o

f Spe

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% Failed in Group

Figure ES-2. Regulator failures by regulator manufacturer.

Figure ES-3, which shows the number of failed regulators for the four environmental conditions, shows a higher percentage of failures from a warm, dry environment. With the number of samples being reasonably significant (much greater than ten units), the fact that nearly half of the warm, dry regulators failed to meet the test criteria is also significant. While internal and external corrosion may be considered a significant failure mechanism, drying or hardening of the elastomeric components may be more significant. Several regulators that were identified as “failures” were selected for detailed failure analysis to determine possible failure mechanisms and environmental variables that contributed to the failure. Findings from the failure analysis indicate a few possible trends as to why some regulators did not meet the test criteria. In particular, one second-stage regulator did not relieve because of excessive dirt and spider webs blocking the relief opening. This is not a manufacturing issue but rather a maintenance or installation issue and would not be indicative of any problems related to regulator age, environment, or manufacturer. This problem is not expected for regulators that are properly inspected and maintained. For the regulators that were disassembled and analyzed, debris within the regulator body was the single most common potential cause for elevated regulator lock-up and/or leaks through the PRD. Some of the debris found appears to be corrosion products (from piping or containers), but other debris appears to be related to regulator manufacturing. For example, a first-stage regulator contained machining turnings inside the body of a regulator, with some pieces stuck on the

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control disk seat. This debris was too large to get through the inlet screen of the regulator and appeared to be from the regulator manufacturing process.

21 out of 6529 out of 10113 out of 47

29 out of 61

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Figure ES-3. Regulator failures by regulator environment.

Other regulators showed some damage to the regulator seat disc which could have led to high lock-up pressures. For example, a single-stage regulator appeared to be in good condition during initial external and internal (visual through the bonnet opening) examinations. However, when examined more closely significant degradation of the seat disc was found. The seat disc appeared to have material losses more significant than what would be expected solely from the compression set. In addition, a significant amount of debris was found between the orifice and seat disc which could be attributed to the material lost from the seat disc. While this degradation is significant, this regulator was 43 years old when removed from service. This unit was in service well beyond the recommended service life of either the 15-year period or the more recent periods of 20 or 25 years. For several other regulators no specific cause for the regulator “failure” could be determined. Possible causes included a slash on the diaphragm and a scratch on the regulator shaft that mates with the o-ring seal, however all other locations within the regulator body appeared to be in working order and free from significant debris.

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Table of Contents Page

Acknowledgments.......................................................................................................................... iii Executive Summary ........................................................................................................................ v 1.0 Program Objectives and Introduction ....................................................................................... 1 2.0 Background............................................................................................................................... 3

2.1 How a Regulator Works........................................................................................................ 4 2.2 Types of Regulators .............................................................................................................. 6 2.3 Propane Vapor Delivery System Configurations.................................................................. 7

3.0 Literature Review (GTI) ........................................................................................................... 9 3.1 Approach............................................................................................................................... 9 3.2 Literature Search Results ...................................................................................................... 9

4.0 Regulator Gathering, Test Protocol Development, and Test Rig Design (Task 2)................. 13 4.1 Gathering Regulator Samples ............................................................................................. 13 4.2 Development of Test Protocol ............................................................................................ 22 4.3 Design and Construction of Test Rig.................................................................................. 27

5.0 Regulator Selection, Testing, and Evaluation (Task 2) ......................................................... 33 5.1 Regulator Selection............................................................................................................. 34 5.2 Visual Inspection of Regulators.......................................................................................... 37

5.2.1 Visual External Inspection........................................................................................... 37 5.2.2 Visual Internal Inspection ............................................................................................ 37 5.2.3 Regulator Adjustment .................................................................................................. 38

5.3 Regulator Test Results and Evaluation ............................................................................... 38 5.3.1 Summary of Lock-up Test Results .............................................................................. 43 5.3.2 Summary of Pressure Relief Test Results.................................................................... 57 5.3.3 Effects of Manufacturer on Regulator Performance.................................................... 69 5.3.4 Effects of Environment on Regulator Performance.................................................... 74 5.3.5 Causes of Regulator “Failures”.................................................................................... 80

6.0 Inspections of “Failed” Regulators (Task 3)........................................................................... 91 7.0 Conclusions............................................................................................................................. 95

7.1 Literature Survey ................................................................................................................ 95 7.2 Effects of Age on Regulator Performance .......................................................................... 96 7.3 Effects of Manufacturer on Regulator Performance........................................................... 97 7.4 Effects of Environment on Regulator Performance............................................................ 97 7.5 Inspections of “Failed” Regulators ..................................................................................... 97

APPENDICES Appendix A – Literature Review of Low Pressure Propane Vapor Regulators by GTI............. A-1

Appendix B – Comments on Regulator Test Protocol and Associated Justification for the Revised Protocol ..........................................................................................................................B-1

Appendix C – Inspections of “Failed” Regulators.......................................................................C-1

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List of Tables Page

Table 1. Types of propane regulators. ............................................................................................ 6 Table 2. Number and location of regulators received for the study.............................................. 15 Table 3. Overview of first-stage regulator performance............................................................... 39 Table 4. Overview of second-stage regulator performance. ......................................................... 40 Table 5. Overview of integral two-stage regulator performance.................................................. 41 Table 6. Overview of single-stage regulator performance............................................................ 41 Table 7. First-stage regulators that did not meet the UL 144 lock-up criteria for new

regulators..................................................................................................................... 44 Table 8. Second-stage regulators that did not meet the UL 144 lock-up criteria for new

regulators..................................................................................................................... 49 Table 9. Integral two-stage regulators that did not meet the UL 144 lock-up criteria for

new regulators. ............................................................................................................ 52 Table 10. Single-stage regulators that did not meet the UL 144 lock-up criteria for

new regulators. ............................................................................................................ 55 Table 11. First-stage regulators that did not meet the UL 144 PRD criteria for new regulators. . 58 Table 12. Second-stage regulators that did not meet the UL 144 PRD criteria for new regulators.

..................................................................................................................................... 64 Table 13. Integral two-stage regulators that did not meet the UL 144 PRD criteria for

new regulators. ............................................................................................................ 65 Table 14. Single-stage regulators that did not meet the UL 144 PRD criteria for new

regulators..................................................................................................................... 67 Table 15. Summary table of failed regulators............................................................................... 83 Table 16. Regulator failures by type............................................................................................. 85 Table 17. Regulator failures by manufacturer. ............................................................................. 86 Table 18. Regulator failures by age. ............................................................................................. 87 Table 19. Regulator failures by environmental condition. ........................................................... 88 Table 20. Regulators selected for failure analysis. ....................................................................... 91

List of Figures Page

Figure ES-1. Regulator failures by age........................................................................................ viii Figure ES-2. Regulator failures by regulator manufacturer........................................................... ix Figure ES-3. Regulator failures by regulator environment............................................................. x Figure 1. Components of a typical regulator. ................................................................................. 3 Figure 2. Positive back pressure regulator. ..................................................................................... 5 Figure 3. Pressure/flowrate chart. ................................................................................................... 5 Figure 4. Two-stage system with relief in first-stage regulator. ..................................................... 8 Figure 5. Two-stage system with separate relief valve on supply line. .......................................... 8 Figure 6. Map illustrating climate regions and source locations of collected regulators. ............ 16 Figure 7. Age distribution of test regulators. ................................................................................ 16 Figure 8. Source environments of test regulators. ........................................................................ 17 Figure 9. Source locations of test regulators................................................................................. 17 Figure 10. Type distribution of test regulators.............................................................................. 18 Figure 11. Manufacturer distribution of test regulators. ............................................................... 18

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Figure 12. Tag lacking information. ............................................................................................. 20 Figure 13. Tag with sufficient information................................................................................... 21 Figure 14. Regulator test protocol. ............................................................................................... 24 Figure 15. Regulator test rig schematic. ....................................................................................... 28 Figure 16. Regulator test stand — front view............................................................................... 29 Figure 17. Regulator test stand — rear view. ............................................................................... 29 Figure 18. Compressor for test air supply..................................................................................... 30 Figure 19. Regulator datasheet. .................................................................................................... 31 Figure 20. Average and 95% upper confidence bounds for first-stage regulators with

100 psi inlet pressure. ....................................................................................................... 36 Figure 21. Average and 95% upper confidence bounds for second-stage regulators with

10 psi inlet pressure. ......................................................................................................... 36 Figure 22. Lock-up pressures and age for 10 psi first-stage regulators at 100 psig inlet

pressure. ............................................................................................................................ 44 Figure 23. Lock-up pressures and age for 10 psi first-stage regulators at 25 psig inlet

pressure. ............................................................................................................................ 45 Figure 24. Lock-up pressures and age for 10 psi first-stage regulators at 250 psig inlet

pressure. ............................................................................................................................ 45 Figure 25. Lock-up pressures and age for 5 psi first-stage regulators at 100 psig inlet

pressure. ............................................................................................................................ 46 Figure 26. Lock-up pressures and age for 5 psi first-stage regulators at 25 psig inlet

pressure. ............................................................................................................................ 46 Figure 27. Lock-up pressures and age for 5 psi first-stage regulators at 250 psig inlet

pressure. ............................................................................................................................ 47 Figure 28. Lock-up pressures and age for 15 psi first-stage regulators at 100 psig inlet

pressure. ............................................................................................................................ 47 Figure 29. Lock-up pressures and age for 15 psi first-stage regulators at 25 psig inlet pressure. 48 Figure 30. Lock-up pressures and age for 15 psi first-stage regulators at 250 psig inlet

pressure. ............................................................................................................................ 48 Figure 31. Lock-up pressures and age for second-stage regulators at 10 psig inlet pressure. ...... 50 Figure 32. Lock-up pressures and age for second-stage regulators at 5 psig inlet pressure. ........ 50 Figure 33. Lock-up pressures and age for second-stage regulators at 15 psig inlet pressure. ...... 51 Figure 36. Lock-up pressures and age for integral two-stage regulators at 100 psig inlet

pressure. ............................................................................................................................ 52 Figure 35. Lock-up pressures and age for integral two-stage regulators at 25 psig inlet pressure.

........................................................................................................................................... 53 Figure 36. Lock-up pressures and age for integral two-stage regulators at 250 psig inlet

pressure. ............................................................................................................................ 53 Figure 37. Lock-up pressures and age for single-stage regulators at 100 psig inlet pressure....... 56 Figure 38. Lock-up pressures and age for single-stage regulators at 25 psig inlet pressure......... 56 Figure 39. Lock-up pressures and age for single-stage regulators at 250 psig inlet pressure....... 57 Figure 40. Start-to-discharge pressures and age for 10 psi first-stage regulators. ........................ 59 Figure 41. Reseat pressures and age for 10 psi first-stage regulators........................................... 59 Figure 42. Start-to-discharge pressures and age for 5 psi first-stage regulators. .......................... 60 Figure 43. Reseat pressures and age for 5 psi first-stage regulators. ............................................ 60 Figure 44. Start-to-discharge pressures and age for 15 psi first-stage regulators. ........................ 61

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Figure 45. Reseat pressures and age for 15 psi first-stage regulators........................................... 61 Figure 46. Start-to-discharge pressures and age for second-stage regulators. .............................. 62 Figure 47. Reseat pressures and age for second-stage regulators. ................................................ 63 Figure 48. Start-to-discharge pressures and age for integral two-stage regulators....................... 66 Figure 49. Reseat pressures and age for integral two-stage regulators......................................... 66 Figure 50. Start-to-discharge pressures and age for single-stage regulators. ............................... 68 Figure 51. Reseat pressures and age for single-stage regulators. ................................................. 68 Figure 52. Lock-up pressures and manufacturer for 10 psi first-stage regulators at 100 psig

inlet pressure. .................................................................................................................... 69 Figure 53. Start-to-discharge pressures and manufacturer for 10 psi first-stage regulators. ........ 70 Figure 54. Reseat pressures and manufacturer for 10 psi first-stage regulators. .......................... 70 Figure 55. Lock-up pressures and manufacturer for second-stage regulators at 10 psig inlet

pressure. ............................................................................................................................ 71 Figure 56. Start-to-discharge pressures and manufacturer for second-stage regulators. .............. 71 Figure 57. Reseat pressures and manufacturer for second-stage regulators. ................................ 72 Figure 58. Lock-up pressures and manufacturer for single-stage regulators at 100 psig inlet

pressure. ............................................................................................................................ 72 Figure 59. Start-to-discharge pressures and manufacturer for single-stage regulators................. 73 Figure 60. Reseat pressures and age for single-stage regulators. ................................................. 73 Figure 61. Regulator failures by regulator manufacturer.............................................................. 74 Figure 62. Lock-up pressures and environment for 10 psi first-stage regulators at 100 psig inlet

pressure. ............................................................................................................................ 75 Figure 63. Start-to-discharge pressures and environment for 10 psi first-stage regulators. ......... 76 Figure 64. Reseat pressures and environment for 10 psi first-stage regulators. ........................... 76 Figure 65. Lock-up pressures and environment for second-stage regulators at 10 psig inlet

pressure. ............................................................................................................................ 77 Figure 66. Start-to-discharge pressures and environment for second-stage regulators. ............... 77 Figure 67. Reseat pressures and environment for second-stage regulators. ................................. 78 Figure 68. Lock-up pressures and environment for single-stage regulators at 100 psig inlet

pressure. ............................................................................................................................ 78 Figure 69. Start-to-discharge pressures and environment for single-stage regulators.................. 79 Figure 70. Reseat pressures and age for single-stage regulators. ................................................. 79 Figure 71. Regulator failures by regulator environment............................................................... 80 Figure 73. Regulator “failures” by type of regulator. ................................................................... 85 Figure 73. Regulator “failures” by regulator manufacturer. ......................................................... 86 Figure 74. Regulator “failures” by regulator age.......................................................................... 87 Figure 75. Regulator “failures” by type of environment. ............................................................. 88 Figure 76. Regulator 711 — blocked pressure relief. ................................................................... 92 Figure 77. Regulator 571 — machining turnings found inside regulator. .................................... 92 Figure 78. Regulator 383 — seat disc........................................................................................... 93

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Terms and Acronyms

Btu British thermal unit cfh cubic feet per hour cfm cubic feet per minute DOT United States Department of Transportation in wc inches of water column NFPA National Fire Protection Association NPGA National Propane Gas Association PERC Propane Education & Research Council PRD pressure relief device psi pound per square inch UL Underwriters Laboratories

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1.0 PROGRAM OBJECTIVES AND INTRODUCTION Anecdotal evidence suggests that the natural gas industry effectively and safely uses low pressure regulators in field service for time periods exceeding 30 years. Yet in the LP gas (propane)∗ industry, regulator manufacturers provide regulators that have limited field evaluation capability and regularly carry a 15-year replacement recommendation. Recently, three propane regulator manufacturers have extended the service-life recommendation of some propane regulators. For example, ECII/RegO® and Sherwood literature recommends a service life of 25 years for first-and second-stage regulators manufactured after 1995 and a recommended service life of 15 years for all other regulators. Catalogs from Fisher recommend regulator replacement at 20 years. Fisher also recommends replacing any regulators “that have experienced conditions (corrosion, underground systems, flooding, etc.) that would shorten their service life.” The Propane Education & Research Council (PERC) is interested in determining whether there is scientific or engineering support for the 15-year replacement recommendation, as well as for the recently extended service life recommendation for some models. PERC requested Battelle’s assistance in developing data and analyses to better understand the performance of in service low pressure propane vapor regulators. The objectives of this program are to evaluate the performance, durability, and service life of low pressure propane vapor regulators through the following tasks:

Task 1. Review and summarize current US, European, Australian, and Japanese propane regulator manufacturer’s literature on recommended service life and the basis for all service life recommendations;

Task 2. Gather and test first- and second-stage regulators pulled from service to identify if they exhibit catastrophic failure modes that could result in potential safety problems; and

Task 3. Inspection of selected regulators that failed one or more test criteria. This report summarizes the results of an experimental program in which low pressure propane vapor regulators ranging in age from 1 to over 50 years were collected from across the United States and were subjected to a series of tests intended to characterize their performance. This is Volume 1 of a two volume report on the results of the program. This first volume is a summary and analysis of the test results. The second volume provides a detailed description of the results of each regulator investigated, including the test datasheets and photos. Volume 1 is organized as follows:

• Background • Literature Review • Overview of Regulator Collection, Test Protocol Development, and Test Rig Design • Regulator Selection, Testing, and Evaluation • Inspection of Failed Regulators

∗ The terms “LP gas” and “propane” are used interchangeably in the industry and this report.

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• Appendix A – GTI Literature Review • Appendix B – Comments on Regulator Test Protocol Development • Appendix C – Inspections of “Failed” Regulators.

The summary and conclusions of this program are provided in the Executive Summary at the beginning of the document.

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2.0 BACKGROUND Propane regulators are designed to reduce gas supply pressures to a desired operating pressure range. Systems installed today consist of two-stage regulation in which a first-stage regulator reduces supply pressure to near 10 psig, and a second-stage regulator further reduces the pressure to typical appliance pressures, nominal 11 inches of water column (in wc). This two-stage system can also be combined into one regulator known as an integral two-stage regulator. All LP gas regulators are installed according to the National Fuel Gas Code (NFPA 54), Standard for the Storage and Handling of Liquefied Petroleum Gases Code (NFPA 58), and any local requirements. Components of a typical regulator are shown in Figure 1.

Figure 1. Components of a typical regulator.1

Selection of regulators is based on the desired gas supply pressure as well as the flow capacity (defined in Btu/hr) required by the total gas load. Regulators are rated at the amount of Btu/hour they can deliver at a specific inlet and outlet pressure. If a regulator will supply multiple appliances, the Btu requirements for each appliance are added to identify the regulator capacity necessary for that particular application. Flow capacity tables and charts are provided by the regulator manufacturers to aid in this selection process.

1 From USDOT/PHMSA Office of Pipeline Safety Chapter IX http://ops.dot.gov/regs/small_lp/Chapter9.htm

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To achieve the desired outlet pressures, many regulators can be adjusted to the specified set point for that system. In adjustable regulators, the outlet pressures can be changed by removing the bonnet cap and adjusting the screw found inside. Some regulators are factory set to the specified outlet pressure and therefore cannot be re-adjusted by the marketer or consumer. Underwriters Laboratories Standard UL 144 is the listing document for construction and performance of LP-Gas Regulators. UL 144 defines temperature/pressure ratings, relief valve performance, materials of construction, lock-up ranges, adjustment range, operation/performance and marking requirements. This standard was used as the basis for this test program.

2.1 How a Regulator Works

The low pressure LP gas regulators are positive back pressure regulators used for first-stage, second-stage, single-stage, and integral two-stage regulation. The positive back pressure regulator provides good flow characteristics over a wide range of inlet pressures. The regulator delivery pressure is affected by the changes in inlet pressure, as well as demand from a downstream appliance(s). The seat disc is on the downstream side of the seat. As inlet pressure rises, the delivery pressure rises; as inlet pressure drops, delivery pressure drops. Figure 2 illustrates the basic components related to how a regulator works, with the following text from the DOT website referenced below1.

Gas enters through the inlet and flows through an orifice (A). As pressure builds under the diaphragm (B), which moves upward and pushes the seat disc attached to the lever assembly (D) against the inlet nozzle or orifice (A). At the same time adjusting spring (C) compresses, limiting the travel of the diaphragm. If there is no gas demand, the seat disc will stay against the nozzle and gas flow will stop. This is called lock-up. Lock-up outlet pressures are always greater than the set point pressure as illustrated in Figure 3. When gas demand from the appliance begins, pressure under the diaphragm (B) is reduced, the adjustment spring pushes the lever/seat disc away from the seat and gas flow is allowed through the seat. The diaphragm will continue to sense the pressure under it, and will compress or relax the adjustment spring, which will move the seat lever/seat disc assembly against or away from the seat. This constant movement controls the pressure to downstream regulators or appliances. The design of the adjustment spring determines the pressure setting.

1 From US DOT/PHMSA Office of Pipeline Safety Chapter IX http://ops.dot.gov/regs/small_lp/Chapter9.htm

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Figure 2. Positive back pressure regulator.1

Figure 3. Pressure/flowrate chart.2

1 From US DOT/PHMSA Office of Pipeline Safety Chapter IX http://ops.dot.gov/regs/small_lp/Chapter9.htm 2 From US DOT/PHMSA Office of Pipeline Safety Chapter IX http://ops.dot.gov/regs/small_lp/Chapter9.htm

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Relief Operation A relief valve is installed in all second- and integral two-stage regulators and most first-stage regulators. The relief valve is designed to protect downstream equipment and appliances from overpressure and operates according to UL 144 requirements. Relief valve operation is described on the DOT website, referenced below with the following text from the DOT website referenced below1.

When gas enters through orifice (A), as described in Figure 2 and downstream demand is reduced or stops, the lever/seat disc (D) will move toward the nozzle to the lock-up position. If the regulator seat disc cannot fully contact the orifice (A), pressure will continue to build until diaphragm (B) moves up to the point where relief spring (E) begins to compress, allowing gas flow through the relief area into the bonnet and out through the vent (G). The relief valve will automatically close once the pressure under the diaphragm is reduced to a nominal pressure.

2.2 Types of Regulators

Regulator systems control gas pressure from the container to the appliance, reducing the container pressure to the required outlet pressure. There are several types of regulators that can be used to achieve the desired system performance and range in style and combinations of regulators and are presented in Table 1.

Table 1. Types of propane regulators.

Regulator Type Description Example

Single-stage • A single regulator mounted on the propane container with a line running directly to the appliance(s)

• Limited to small portable appliances and outdoor cooking appliances with maximum input ratings of 100,000 Btu/hr per NFPA 58, 1995 Edition.

• Designed for propane vapor service to reduce container pressure to 1.0 psig or less (typically 11in wc)

• Listed by Underwriters Laboratories or equivalent for use in propane with an inlet pressure rating of 250 psig.

• Utilizes a type I relief valve which has a limited capacity; operating range is from 18.7 in to 33 in wc

• Per the 1995 Edition of NFPA 58, single-stage regulators may no longer be installed on fixed piping systems.

1 From US DOT/PHMSA Office of Pipeline Safety Chapter IX http://ops.dot.gov/regs/small_lp/Chapter9.htm

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Regulator Type Description Example

First-Stage • A pressure regulator for propane vapor service designed to reduce container pressure to 5, 10, 15, or 20 psig (typically 10 psig).

• Used as the container regulator in a two-stage system.

• This regulator is UL listed for use as a first-stage regulator with an inlet pressure rating of 250 psig.

• This regulator utilizes a type I relief valve which is a limited capacity; operating range is from 14 psig to 25 psig.

Second-Stage • A pressure regulator for propane vapor service designed to reduce first-stage regulator outlet pressure to 14" water column or less (typically 11in wc)

• This regulator is UL listed for use in propane with an inlet pressure marked at 10 psig, but a rating of 250 psig.

• This regulator utilizes a type II relief valve - a high capacity type for final stage regulators; operating range is from 18.7 in to 33 in wc

Integral Two-Stage

• A pressure regulator that combines both a high pressure and a second-stage regulator into a single unit.

• UL listed with a 250 psig inlet pressure rating, no relief in the first-stage section and a type II relief valve in the second-stage section.

2.3 Propane Vapor Delivery System Configurations

Prior to 1995, many propane systems utilized one single-stage regulator to reduce container pressures to appliance pressures of 11 in wc. However, in the event of regulator failure it was possible for appliances to see container pressures. To enhance the safety of propane systems, two-stage regulation was mandated in the 1995 Edition of NFPA 58. According to this edition of NFPA 58, all new domestic fixed pipe installations must use either a two-stage system or an integral two-stage regulator. Single-stage regulators may no longer be installed on these systems. To assist in phasing out single-stage regulation systems, there are ongoing state programs that provide rebates to local marketers for removing single-stage regulation systems and replacing with two-stage regulation.

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A two-stage propane vapor delivery system combines a first-stage regulator and second-stage regulator, integral two-stage regulator, or an automatic changeover regulator. In propane systems rated for less than 500,000 Btu/hr, the first-stage regulators typically have an integral relief valve as shown in Figure 4.

Figure 4. Two-stage system with relief in first-stage regulator.1

Two-stage regulator systems with a first-stage regulator rated at more than 500,000 BTU/HR set at 10 psig or less, typically do not have an integral relief valve. In this case the first-stage regulator is permitted to have a separate relief valve. It must operate within specified start-to-discharge limits of UL 144 (140%-250%) of the regulator set pressure. The second-stage will supply the required appliance pressure. This type of system is depicted in Figure 5.

Figure 5. Two-stage system with separate relief valve on supply line.2

1 From US DOT/PHMSA Office of Pipeline Safety Chapter IX http://ops.dot.gov/regs/small_lp/Chapter9.htm 2 From US DOT/PHMSA Office of Pipeline Safety Chapter IX http://ops.dot.gov/regs/small_lp/Chapter9.htm

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3.0 LITERATURE REVIEW (GTI) With the recently extended service-life recommendation of some propane regulators, a literature review was important to determine if there was scientific or engineering support for a 15-year replacement recommendation, and if an extended service life recommendation for some models was warranted. The objective was to provide an annotated review of available information worldwide on low-pressure propane regulators with focus on recommended service life and to the extent possible the basis for cited recommendations.

3.1 Approach

U.S. manufacturers market low-pressure propane regulators worldwide. These regulators are constructed to comply with U.S. standards and then separately certified for use in overseas markets. For this reason, the focus of this review was on U.S. manufacturers, specifically the three companies that occupy a majority of the regulator market share: Fisher, RegO®, and Sherwood. GTI reviewed manufacturers’ literature from Fisher, RegO®, and Sherwood and concentrated on additional research conducted by the Korean Gas Safety Corporation. In addition, GTI reviewed relevant codes and standards, and reviewed the abstracts of peer-reviewed research on materials. GTI supplemented this review with follow-up discussion with materials and analytical personnel, and with the regulator manufacturers.

3.2 Literature Search Results

The areas of focus of the literature search included elastomers, metals, propane composition, codes and standards, manufacturer’s literature, and missing data. The complete GTI report is provided in Appendix A. This section highlights the findings of GTI’s literature search.

• The literature review was not able to document scientific or engineering support for a service-life recommendation of 15 years or greater. The findings of the literature review suggest further research in the use and variability of plasticizers and extenders in the rubber composition of propane regulator components; the long-term effect a propane operating environment has on elastomer and spring performance; and the effect of propane contaminants and off-specification gas on U.S. propane regulator performance.

• In “Aging Characteristics of Low Pressure LPG Regulators for Domestic Use”1, results showed that in general the safety devices of the low-pressure regulators deviated from like-new operation after a year of service and deviated from the discharge start and reset

1 Jeong-Rock Kwon, Young-Gyu Kim Gas Safety R&D Center, Korea Gas Safety Corporation, “Aging Characteristics of Low Pressure LPG Regulators for Domestic Use”, May 1999.

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pressures of the new regulators. Overall, the operating and closing pressures also deviated from the pressure range of the new regulators after a year of service. A 6-year service life was determined:

- Testing of diaphragms from the propane regulators in the field found a loss of tensile strength and decreased range of motion after 5 years of service. Researchers suspect a hardening of the diaphragms due to leaching of plasticizers from rubber materials over time. The authors called for further research to improve diaphragm durability and reliability, to investigate the effect of plasticizer extraction from rubber materials on diaphragm performance, and the development of new rubber materials with improved rubber characteristics and properties.

- Testing of propane regulator springs from the field found a loss in tensile strength after a 7 year service life. The authors called for research on various aspects of springs, including the surface treatment on the ending parts of the spring, quality control in the manufacturing, and reinforcement of durability characteristics.

- None of the regulators tested were from U.S. manufacturers. Research is warranted to investigate the long-term effect a propane operating environment has on elastomer and spring performance.

• A review of elastomers reference literature, “The Vanderbilt Rubber Handbook -13th Edition”1, and “Rosato’s Plastics Encyclopedia and Dictionary”2, found that additives, particularly plasticizers and extenders, can leach out over time, resulting in physical changes in size, elongation, and tear strength. In regulators, elastomers are used in valve seat discs and diaphragms. Research is warranted to assess the use and variability of plasticizers and extenders in the rubber composition of propane regulator components.

• In “Investigation of Portable or Handheld Devices for Detecting Contaminants”3, findings indicate that while propane for domestic use meets commercial grade specifications, contamination occurs in small quantities in the supply chain over time. Further, the impact of propane contaminants and off-specification gas is not well documented. Research is warranted to investigate the effect of propane contaminants and off-specification gas on U.S. propane regulator performance.

• Underwriters Laboratories’ UL 144 LP-Gas Regulators is the current performance standard for LP-Gas regulators and is designed for new regulators, not regulators that have been in the field. UL 144 does not address the issue of service or useful life. Test requirements for materials such as elastomers are also found in UL 144. Tests include propane compatibility (with n-hexane as the test fluid), accelerated aging (in heated air), and low temperature exposure (in cooled air). UL 144 does not give references on using n-hexane as a surrogate for propane. UL 144 does not address the varying composition of propane, therefore the effect of off-specification propane or even the broad range of on-specification compositions is unknown.

1 Ohm, Robert F., “The Vanderbilt Rubber Handbook -13th Edition”, R.T. Vanderbilt Company, Inc., 1990. 2 Rosato, Dominick V., “Rosato’s Plastics Encyclopedia and Dictionary”, Oxford University Press, 1993. 3 Southwest Research Institute, “Investigation of Portable or Handheld Devices for Detecting Contaminants in LPG, Docket 11296”, for the Propane Education and Research Council, Washington, D.C., 2005.

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• Codes and standards that reference UL 144, including NFPA 54: National Fuel Gas Code, NFPA 58: Liquid Petroleum Gas Code and ANSI Z21.18a-2001/CSA 6.3a Gas Appliance Pressure Regulators do not address useful or service life of propane system components.

• A review of U.S. manufacturers’ literature found: - RegO® recommends regulator service life of 25 years for regulators (except single-

stage) manufactured after 1995; all other regulators have a recommended service life of 15 years.

- Fisher recommends regulator replacement at 20 years, or over 15 years of age for regulators that have experienced conditions (corrosion, underground systems, flooding, etc.) that would shorten their service life.

- Sherwood recommends regulator replacement after 15 years; however, Sherwood has recently posted a statement on their website that now recommends a 25-year life on some models1.

• Typical materials identified in the literature that are used in propane regulators include zinc or die cast aluminum bodies, chromate coatings, nitrile rubber and other synthetic polymers, and stainless steel springs.

• Service life attributes, or manufacturers’ stated features that influence service life, include a corrosion resistant relief valve seat (Fisher); stainless steel relief valve spring and retainer (Fisher); and painted, heavy-duty zinc (body and bonnet) resists corrosion and gives long-life protection, even under “salty air” conditions. (RegO®).

• All three manufacturers’ literature reference National Propane Gas Association (NPGA) documents in discussions related to installation, inspection, maintenance, and safety. NPGA no longer supports these documents and has released these documents to the public domain provided that they are not attributed to NPGA. Discontinued documents that are referenced include:

- NPGA Installation and Service Guide Book #4003, - NPGA Propane Safety and Technical Support Manual Bulletin T403, - NPGA Safety Pamphlet 306 “LP-Gas Regulator and Valve Inspection and

Maintenance”, - NPGA LPG Safety Handbook #0001, and - NPGA Bulletin #133-80.

These documents can no longer be referenced as NPGA documents and efforts should be made by the manufacturers to acknowledge and correct this within their product literature.

1 http://www.sherwoodvalve.com/products.htm/Regulator 25 YR Ser Life Rev 2 3-25-04.pdf

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4.0 REGULATOR GATHERING, TEST PROTOCOL DEVELOPMENT, AND TEST RIG DESIGN (TASK 2)

Propane gas regulator replacement requirements are based upon assumptions of the severity of the service environment and how much damage is caused by the service environment. However, without a systematic evaluation of regulators from service, there has been no way to know if these assumptions are valid or how conservative the requirements are. The underlying goal of this program was to collect a large set of regulators representing a variety of ages, types, manufacturers, service environments and service conditions and to test them to better understand real world performance and the scientific merit behind the regulator replacement requirements. This goal was accomplished by collecting regulators of various ages, makes, and models that have been in service across the United States and subjecting the regulators to a series of tests based on UL 144 that demonstrate their performance. This section of the report gives a brief summary of the collection process, test protocol development, and test rig design. It is followed by an in-depth review of regulator test results and observations. To successfully complete the low pressure propane regulator performance testing program the primary goals were to:

1. Gather a statistically valid sample of first-and second-stage regulators (various ages, makes, models, and regional/environmental conditions) for performance testing.

2. Develop a test protocol valid for regulators that have been recently removed from service and gather feedback from industry members on this protocol.

3. Design and construct a test rig to conduct the regulator performance testing.

4. Tabulate performance test data in a data base and analyze data to assist in the determination of expected regulator service life. Trends were examined between various geographic locations, regulator ages, and manufacturers.

All of these goals are discussed further in the subsequent sections of this report.

4.1 Gathering Regulator Samples

Efforts were made to obtain a reasonable age, type, and manufacturer distribution of residential low pressure propane vapor regulators from a range of environmental conditions typical of the United States. Battelle worked with the NPGA, PERC, state propane associations, and industry consultant Larry Osgood to acquire over 700 regulators from propane marketers located throughout the United States. Announcements were placed in weekly NPGA newsletters and PERC weekly email newsletters detailing project requirements and contact information. In addition, the project background and needs were presented to members at the NPGA Technology and Standards Committee November 2004 meeting.

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Battelle also contacted a majority of the state propane associations and over 450 individual propane marketers across the country via telephone and email to request their participation in this study. Propane marketers were requested to provide regulators from different manufacturers, ages, service uses (residential and commercial), environmental conditions, and makes/models of regulators that recently been removed from service (within one month of shipping to Battelle). The requirement that the regulators be recently removed from service was to reduce the possibility that a regulator was affected by the internals being exposed to air for extended periods of time. Regulators could have been removed from service for a variety of reasons: failure of the regulator to perform, change or loss of customer account, end of recommended service life. Marketers interested in participating were sent shipping supplies consisting of large, plastic zip-lock bags and information tags. The information tags requested the following information:

• Submittal Date • Contact Information • Regulator Manufacturer • Model Number • Regulator Type • Year Installed • Date Removed from Service (must be within the past month) • Regulator Location • Geographic Service Area • Reason for Regulator Removal • General Regulator Operating Conditions (location at tank; location at building; types of

appliances within household) Battelle asked that the marketers fill out an information tag for each regulator and attach it to the regulator prior to shipping. From this effort we received a good response; approximately 80 different propane marketers across the country promising to provide over 1000 regulators. A total of 773 regulators were received for evaluation in this program. The 773 regulators were supplied by 49 different marketers in 27 different states, with a large majority (~56%) coming from South Dakota, Mississippi, and Iowa. The list of states and the number of regulators provided from each state is provided in Table 2. The collection of the regulators encompassed the following conditions and environments

• 1 to 50+ years in age • 4 different service environments • 27 different source locations • 4+ different regulator manufacturers • 4 types of regulators

The collection effort specifically targeted first-stage, second-stage, and integral two-stage regulators to examine the assumptions behind the 15-year replacement recommendations. A sampling of single-stage regulators was also collected and tested; however, since 1995 these

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regulators have not been allowed to be placed into service and therefore the testing efforts did not focus on their performance.

Table 2. Number and location of regulators received for the study.

State # of Regulators Received AK 17 AL 1 AZ 4 CA 14 CO 5 FL 10 IA 162 IL 3 IN 32 KS 5 KY 6 MA 2 ME 18 MI 19

MO 2 MS 87 NC 15 NH 10 NJ 12 NY 21 OH 8 PA 27 SC 47 SD 184 VA 33 WA 23 WI 4

Unknown 2 Total 773

Figure 6 illustrates the different states and four environmental regions from which regulators were collected. As such, it provides a good basis for examining some of the assumptions that are the foundation for the service life of low pressure propane vapor regulators. Figures 7 through 11 summarize the characteristics and subsets of the regulators which were selected for detailed testing and evaluation. Figure 7 compares the ages of the regulator test population. The majority of the regulators collected and tested ranged in age from 5 to 20 years, although a few regulators over 50 years old were tested. Thirty of the regulators tested were 5 years old or less, another 49 of the regulators tested were between 5 and 10 years old, 52 were between 10 and 15 years old, and 38 were between 15 and 20 years old.

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* Regulators were also received from Dutch Harbor, Alaska.

Figure 6. Map illustrating climate regions and source locations of collected regulators.

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Figures 8 and 9 compare the service environments and source locations where the regulators were obtained. A majority of regulators obtained for testing were from a cool, dry environment. When the regulator samples were selected for testing, a fairly equal distribution of the four environments was chosen to represent the environments in the United States that could potentially degrade regulator performance. As depicted in Figure 9, approximately 56% of the regulator test samples came from South Dakota, Mississippi, and Iowa.

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Figure 9. Source locations of test regulators.

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Figures 10 and 11 compare the percentage of each regulator type and regulator manufacturer represented in the database. The majority of regulators were from two manufacturers (referred to as Manufacturer A and Manufacturer B) with a nearly equal distribution of first-stage and second-stage regulators received from both manufacturers. Far fewer integral two-stage regulators were received for testing. It is likely we would have received more single-stage regulators had we not focused on collection of regulators designed for two-stage systems.

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Figure 10. Type distribution of test regulators.

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Figure 11. Manufacturer distribution of test regulators.

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Even after Battelle contacted over 450 individual propane marketers, a majority of the state propane associations, and submitted bulletins in NPGA and PERC newsletters there were still marketers that responded they were unaware of the project months later. The regulator collection efforts were slow and difficult. During the collection process a number of issues were identified that could be useful if a similar test program is recommended in the future:

• Collection began in the winter of 2004 – 2005. Many of the propane marketers indicated that they were too busy supplying customers with propane to spend time collecting regulators, filling out the information cards, and shipping the regulators to Battelle.

• The large, nationwide propane marketers had reservations about participating in this testing program. Particularly, some felt the study was flawed since regulators are removed from service based on their condition; not because of an arbitrary age designation. This very fact would affect the results of the study since many of the regulators tested would be defective and/or deteriorating. One marketer felt that a better approach would be to collect a representative sample of regulators from operating systems and develop specific procedures to record data before they are removed and for protection of regulators after removal. They recognized that this undertaking would be very expensive both in terms of manpower and time.

• A number of marketers had an over-abundance of single-stage regulators that they were willing to supply; however not as many first-stage, second-stage, or integral two-stage systems were offered. This is primarily due to the state programs that are providing rebates to LP gas marketers to remove their single-stage systems and replace with two-stage regulation systems.

• For many marketers, they have a policy to destroy regulators immediately after removal and subsequently sell them for scrap. Some marketers were not willing to deviate from this policy to supply regulators for this study primarily due to liability issues.

• Some customers own their own tanks and therefore it would be difficult for the marketer to collect those regulators.

• The background data provided for each regulator ranged from good detail about the regulator and its operation to very little known about the regulator including the regulator type (first, second, or single-stage). This made testing more difficult as we had to verify the regulator type before beginning each test. For older regulators, it was not easy to find this information, and we had to contact the manufacturers with the model and part numbers to verify the regulator type. Figure 12 provides an example of an information tag that is lacking the necessary detail, and Figure 13 provides an example of an information tag with sufficient information.

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Performance, Durability, and Service Life of 20 September 2006 Low Pressure Propane Vapor Regulators Battelle

Figure 12. Tag lacking information.

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Performance, Durability, and Service Life of 21 September 2006 Low Pressure Propane Vapor Regulators Battelle

Figure 13. Tag with sufficient information.

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Performance, Durability, and Service Life of 22 September 2006 Low Pressure Propane Vapor Regulators Battelle

4.2 Development of Test Protocol

Battelle developed a draft test protocol based on the UL 144 Standard for Safety for LP-Gas Regulators and submitted it to regulator manufacturers, equipment vendors, and propane industry members to gather feedback. Those participants that were asked to provide feedback during the regulator test protocol development included:

• David Kalensky, Tim Cole, and Vasilios Soupos, Gas Technology Institute (GTI) • Larry Osgood, Consulting Solutions, PERC’s program monitor • Gary Koch, Koch & Associates, propane industry consultant • Ron Czischke, Underwriters Laboratories (UL) • Sam McTier, McTier Supply • Jim Griffin, Fisher Controls • David Stainbrook, ECII/RegO® • Jeffre Borton, Sherwood Valves • Jim Peterson, Peterson Engineering.

The sections of UL 144 that the review group felt were the most relevant for testing the performance of in-service regulators included:

• Lock-up Test (Section 21 and Table 21.1) • Flow Test (Section 22) • Pressure Relief Test (Section 23) • Relief Capacity Test (Section 24).

Although UL 144 was used as the basis, some tests were combined (Lock-up and Flow Tests) to expedite the testing process as well as modified to better mimic service conditions of the low pressure propane vapor regulators (see Figure 14). According to UL 144, the lock-up pressure limit is 120% to 160% of the outlet pressure for single-stage, integral two-stage, and second-stage regulators and 130% to 150% of the outlet pressure for first-stage regulators. These values were used as criteria to determine the variance in regulator lock-up performance at the various inlet pressures and flow rates. In addition, UL 144 requires that the pressure relief devices start-to-discharge at a pressure between 140% and 250% of the outlet pressure for first-stage regulators and 170% to 300% of the outlet pressure for second-stage, single-stage, and integral two-stage regulators. In addition, the relief device was expected to reseat at a pressure greater than 140% of the outlet pressure for first-stage regulators and greater than 170% of the outlet pressure for second-stage, single-stage, and integral two-stage regulators. These values were used as criteria to determine the performance of the regulator pressure relief devices. The draft documents reviewed by the group contained the regulator testing protocol flowcharts and a narrative of the test procedures and equipment schematics. All participants responded with extremely valuable comments and concerns regarding how the test protocol should be revised.

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Highlights of their comments throughout the review process are listed below:

• Modify the order of the tests as originally proposed to the following: (1) Visual Inspection; (2) Flow/Lock-up Tests; (3) PRD/Flow Capacity Tests.

• Remove the leakage test; the leakage test specified in UL 144 is more for regulator design rather than performance. Replace leakage test with a test to monitor for leaks during Lock-up; essentially block in the regulator during lock-up and monitor for leaks and pressure decay.

• Adjust the regulator prior to conducting the tests so that all regulators can be compared on the same basis (note the initial outlet pressure and screw height before adjustment).

• For the Flow/Lock-up Tests start with an average inlet pressure, then move to the lower inlet pressure, and finish with the higher inlet pressure.

• Flow tests should also include flows that mimic pilot light flows (< 1 cfh). • Basis for regulator “failure” during Lock-up tests should be based on UL 144 Table 21.1;

higher lock-up pressures could blow out pilot lights and is a safety issue. [Note: this was not chosen as a failure during the testing.]

• Rather than use a soapy water solution to detect PRD start-to-discharge, utilize the pressure transducer or a water manometer.

• Make sure to note any contaminants during the visual inspection. A detailed list of all comments received and Battelle’s response are provided in Appendix B along with the various revisions of the test protocol. The final test protocol is provided in Figure 14.

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Figure 14. Regulator test protocol.

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Performance, Durability, and Service Life of 25 September 2006 Low Pressure Propane Vapor Regulators Battelle

Figure 14. Regulator test protocol (continued).

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Performance, Durability, and Service Life of 26 September 2006 Low Pressure Propane Vapor Regulators Battelle

Figure 14. Regulator test protocol (continued).

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4.3 Design and Construction of Test Rig

Battelle designed and constructed a test rig for regulator testing based on the protocol discussed previously. The test rig included a 300 psig air compressor, a number of pressure regulators and pressure transducers, a flow meter, various piping/tubing, and data acquisition system. In addition to the data acquisition system, a data sheet was developed to manually record the test data throughout the test cycle. All testing was conducted at Battelle’s Pipeline Simulation Facility in West Jefferson, Ohio. Figure 15 provides a schematic of the test rig, showing the various pressure control regulators and flow control valves. The computerized data acquisition, control system and solenoid valves helped to prevent accidental over-pressurization of the regulator under test and the pressure instrumentation. During shakedown of the test rig, Battelle identified leakage problems with the solenoid valves that required addition of several check valves (also shown in Figure 15). Figure 16 shows the front view of the test rig, with the pressure control regulators visible near the top of the board, and a regulator under test mounted on the bench. Not shown is the data acquisition and control system located to the left of the bench. Figure 17 shows the back of the test rig, with the flow control valve and control and data wiring. Figure 18 shows the air supply compressor. Figure 19 is an example of the datasheet used for all regulator testing.

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Figu

re 1

5. R

egul

ator

test

rig

sche

mat

ic.

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Figure 16. Regulator test stand — front view.

Figure 17. Regulator test stand — rear view.

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Performance, Durability, and Service Life of 30 September 2006 Low Pressure Propane Vapor Regulators Battelle

Figure 18. Compressor for test air supply.

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Figure 19. Regulator datasheet.

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5.0 REGULATOR SELECTION, TESTING, AND EVALUATION (TASK 2)

All regulators received were labeled, documented, and placed in individually sealed bags. In total, 266 regulators were tested by Battelle using test methods similar to those specified in UL 144 for LP-Gas Regulators (newly manufactured). The details of the test protocol are explained in Section 4.2 of this report. The 266 regulators were subjected to external and internal inspections to identify any significant corrosion, damage, or missing components; lock-up testing at three different inlet pressures and four different flowrates; and pressure relief testing. A database of the test results was compiled and is provided in Volume 2. Included within the database are:

• visual inspection information; • measurements of initial and adjusted outlet pressures; • screw height before and after adjustment; • outlet pressures during lock-up testing; • start-to-discharge, reseat pressures, and flow rate during the pressure relief testing; and • documented leaks or other issues identified during testing.

This has resulted in a comprehensive database that allows direct and detailed comparison of regulator performance. Before the regulators were tested, basic information was recorded on the data sheet and external and internal visual inspections were performed. The purpose of the visual inspections was to identify and document any significant corrosion, damage, or missing components. Prior to lock-up and pressure relief testing, all regulators were adjusted to the manufacturer’s specified outlet pressure. There was much debate regarding whether or not the regulators should be adjusted prior to testing. Some participants in the protocol development felt that adjusting the regulator could influence the test results and as such should be tested as received; however others felt that all regulators needed to be compared on an equivalent basis and should be adjusted to the manufacturer’s specified outlet pressure. It was also identified that it would be helpful to know if a number of regulators are significantly out of adjustment. To compromise, it was decided that the “as received” adjusting screw height and outlet pressure would be measured and recorded and then the regulator adjusted to the manufacturer’s outlet pressure setpoint and the screw height re-measured. Regulator lock-up was measured at three different inlet pressures and recorded in three successive trials for each inlet pressure. Lock-up was recorded for first-stage, integral two-stage, and single-stage regulators at 100 psig, 25 psig, and 250 psig inlet pressures while lock-up for second-stage regulators was recorded at 10 psig, 5 psig, and 15 psig inlet pressures. Additional regulator outlet pressure data was recorded for three additional flowrates: 80 cfh to represent a maximum household flowrate (corresponding to an appliance load of 200,000 Btu/hr), 30 cfh to represent a typical household flowrate (corresponding to an appliance load of 75,000 Btu/hr), and 0.5 cfh to mimic pilot light flowrates. The initial test sequence began with the middle inlet

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pressure and a flowrate of 30 cfh. The flowrates were then cycled down to 0.5 cfh and lock-up at 0 cfh then raised to 80 cfh. After the initial sequence, the tests were repeated two more times starting at a flowrate of 80 cfh and cycling down to lock-up. The later sequence was followed for the low inlet pressure and finally the high inlet pressure before proceeding with the pressure relief tests. The pressure relief device start-to-discharge and reseat pressures of each regulator were measured and recorded in three successive trials for each test. The flow capacity of the relief device was measured between each discharge/reseat sequence. In these tests, the start-to-discharge pressure was measured by slowly pressurizing the regulator until the first indication of air escaping was observed using the flow meter. In many cases the relief device did not open fully until the pressure was increased further. Subsequently, the pressure in the regulator was reduced carefully until no air flow from the pressure relief device was observed. This was recorded as the reseat pressure. After the initial sequence, the start-to-discharge pressure and reseating pressure tests were repeated two more times.

5.1 Regulator Selection

The sample of 266 regulators for testing was chosen in the following manner:

• Operating Environment. Average temperature and humidity data were obtained for each location, based on data from the nearest airport to the city where the regulator was located. The locations were classified into four categories:

- Warm; dry ( > 53°F; < 73% humidity), - Warm; damp ( > 53°F; > 73% humidity), - Cool; dry (< 53°F; < 73% humidity), and - Cool; damp (< 53°F; > 73% humidity).

The criteria of temperature and humidity were chosen to ensure the most even distribution of locations among the categories. An alternative would have been to choose the criteria so that the individual regulators (rather than the locations) were distributed evenly among the categories. This method, however, was not chosen as it would have put undue weight on the locations from which many regulators were obtained.

• Regulator Age. The ages of the regulators were also classified into four categories: less than 10 years, 10-19 years, 20-29 years, and 30 years or greater.

• Regulator Manufacturer. Most of the regulators came from two manufacturers and therefore heavily dominate the sample selection.

• Regulator Type. Initially, regulators were selected from all types (first-stage, second-stage, single-stage, and integral two-stage) that were provided for this study. However, after approximately 30 single-stage regulators were tested, it was decided to remove these from the sample pool. Although single-stage regulators are still in service, they are no longer permitted for new installations per NFPA 58. For this reason, it was decided to focus on test samples consisting only of first-stage, second-stage, or integral two-stage regulators.

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Performance, Durability, and Service Life of 35 September 2006 Low Pressure Propane Vapor Regulators Battelle

A sample of four regulators was drawn from each manufacturer/regulator type/location category/age category combination (or group). In many of these groups there were less than four regulators available, in which case all available regulators in the group were included in the sample. If more than four regulators were available, four were sampled at random. If a regulator from a previous sample did not yield any data, an additional sample from that group was chosen, whenever possible. The reason for regulator removal was not used as a selection criterion. However, 45 of the regulators had been labeled by the submitters as “faulty” or “leaking through”. Fifty-four tested regulators did not have the reason for removal identified by the submitters. Collection of regulators ceased on September 30, 2005 with a total of 773 regulators so that testing of the remaining samples could be completed by mid-November. It was originally proposed that 400 regulators should be tested as part of this program. Unfortunately, due to the slow collection of regulators necessary to get a good sample distribution the test sample size was decreased to 266 regulators. The test sample size was determined from analyzing the test data collected after approximately 200 regulators were tested. The test data were analyzed to determine how many additional regulators should be tested to have a fairly high confidence in the test results. The statistical analysis indicated that the data trends would not change significantly with larger sample populations (for example from 100 to 200, and 200 to 300). As such, it was decided that a total of approximately 300 regulators would be tested to ensure that the project was completed by year end and encompasses a reasonable sample of regulators with varying ages, geographic locations, types, and models. Figure 20 depicts the estimated average and 95% upper confidence bounds for the average value of the outlet pressure at lock-up (0 cfh) for a first-stage regulator with 100 psi of inlet pressure. The solid line represents the current estimate of the average outlet pressure by age. The coarser dotted line represents an estimate of the 95% upper confidence bound for the average outlet pressure based on a total of approximately 300 sampled regulators. The finer dotted line represents an estimate of the 95% upper confidence bound for the average outlet pressure based on a total of approximately 500 sampled regulators. There is negligible difference between the two lines, indicating that there would be little benefit to sampling an additional 200 regulators to fulfill the 400 regulator samples originally planned for testing. Figure 21 shows that the estimated average and 95% upper confidence bounds for the average value of the outlet pressure at lock-up (0 cfh) for a second-stage regulator with 10 psi of inlet pressure. Results for the second-stage regulators are similar to those for the first-stage regulators.

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Performance, Durability, and Service Life of 36 September 2006 Low Pressure Propane Vapor Regulators Battelle

Figure 20. Average and 95% upper confidence bounds for first-stage regulators

with 100 psi inlet pressure.

Figure 21. Average and 95% upper confidence bounds for second-stage regulators

with 10 psi inlet pressure.

Current Avg. Outlet Pressure at Lock-up 95% Upper Confidence Bound (300 regulators) 95% Upper Confidence Bound (500 regulators)

Current Avg. Outlet Pressure at Lock-up 95% Upper Confidence Bound (300 regulators) 95% Upper Confidence Bound (500 regulators)

Lock-up Pressure (psig)

Lock-up Pressure (in wc)

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5.2 Visual Inspection of Regulators

Before the regulators were tested, basic information about each regulator was recorded on the data sheet and external and internal visual inspections were performed. The purpose of the visual inspections was to identify and document any significant corrosion, damage, or missing components to possibly correlate regulator condition with performance issues. Additionally, the regulators were adjusted prior to testing to ensure that all regulators were tested on the same basis for easier comparison of results.

5.2.1 Visual External Inspection

Issues identified from the external visual inspection included: • Corroded regulator body • Missing parts (screws, vent screens, bonnet caps) • Excessive paint • Physical damage to the regulator (holes or cracks in the regulator body) • Removal of fittings (corroded; difficult to remove; could not remove) • Excessive dirt.

If the regulator was missing the bonnet cap it was considered unsuitable for testing. The bonnet cap protects the regulator from dirt, debris, and rain/snow entering the regulator body and possibly affecting regulator performance. Since it could not be determined if contaminants due to the missing bonnet cap or the regulator itself caused any performance issues it was decided to remove these regulators from the test pool. Additionally, several regulators had fittings that were difficult to remove or seized in place. These fittings were removed if it could be done without causing damage to the regulator. Regulators with seized fittings were not tested. Regulators that were corroded or had an accumulation of dirt/debris on the exterior of the regulator were documented but still tested to determine their performance. Those regulators with cracks or holes in the regulator body could not be tested and the regulator damage was documented in the database.

5.2.2 Visual Internal Inspection

Issues identified from the internal visual inspection include: • Cross-threaded adjusting screw • Damage to adjusting screw • Adjusting spring seized in place or stiff • Burred threads • Internal corrosion and/or contaminants (dirt, oil).

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Several regulators had adjusting screws that were seized or stiff and difficult to adjust. These regulators were still tested unless other issues were identified such as leaks through the PRD or the outlet pressure would not stabilize. Regulators that had cross-threaded adjusting screws or damage to the internal components were not tested. Most other regulators with issues identified during the internal inspection were tested and the inspection findings were documented in the database.

5.2.3 Regulator Adjustment

Prior to lock-up and pressure relief testing, all regulators were adjusted to the manufacturer’s specified outlet pressure. There was debate regarding whether the regulators should be adjusted prior to testing. Some participants in the test protocol development felt that adjusting the regulator could influence the test results and as such should be tested as received; however others felt that all regulators needed to be compared on an equivalent basis and should be adjusted to the manufacturer’s specified outlet pressure. It was also identified that it would be helpful to know if a number of regulators are significantly out of adjustment. To address both concerns, it was decided that the “as received” adjusting screw height and outlet pressure would be measured and recorded and then the regulator adjusted to the manufacturer’s outlet pressure setpoint and the screw height re-measured. Some regulators were set by the manufacturer and the adjusting spring could not be accessed to make any adjustments. These regulators were tested as received and noted in the database. During adjustment, some regulators had poor regulation, extremely slow lock-up, or leaked through the regulator. In these instances, the information was noted on the data sheet and the test was stopped.

5.3 Regulator Test Results and Evaluation

This section of the report first provides a summary of the regulator test results and then discusses their possible meaning, interpretation and implications. A general overview of regulator performance is provided in Tables 3 through 6 with more detailed discussions in the subsequent sections.

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Performance, Durability, and Service Life of 39 September 2006 Low Pressure Propane Vapor Regulators Battelle

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End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

ΔO

OO

Spr

ing

lock

ed in

pla

ce; R

egul

ator

mod

el d

oes

not h

ave

an in

tegr

al re

lief v

alve

126

Man

ufac

ture

r A1s

t Sta

ge15

War

m, D

amp

NC

Sub

urba

nE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

OO

OO

OO

O13

1M

anuf

actu

rer B

1st S

tage

13C

ool,

Dry

IAR

ural

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

ΔO

OO

OO

Leak

ed a

t pre

ssur

e ga

uge

fittin

g; ti

ghte

dned

and

con

tinue

d w

ith te

sts

132

Man

ufac

ture

r B1s

t Sta

ge10

Coo

l, D

ryIA

Rur

alE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

ΔO

OO

OO

OM

issi

ng p

ress

ure

gaug

e pl

ug; r

epla

ced

and

cont

inue

d w

ith te

sts

133

Man

ufac

ture

r B1s

t Sta

ge17

Coo

l, D

ryIA

Rur

alE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

OO

OO

OR

egul

ator

mod

el d

oes

not h

ave

an in

tegr

al re

lief v

alve

135

Man

ufac

ture

r A1s

t Sta

ge15

Coo

l, D

ryIA

Rur

alE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

OO

OO

OA

djus

ting

sprin

g fro

zen

145

Man

ufac

ture

r A1s

t Sta

ge**

2W

arm

, Dam

pM

SR

ural

Cha

nged

from

sin

gle

to d

ual r

egul

ator

sys

tem

OO

OO

OO

O15

1M

anuf

actu

rer A

1st S

tage

9W

arm

, Dam

pM

SR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

XM

issi

ng b

onne

t cap

; reg

ulat

or p

erfo

rmed

with

in U

L cr

iteria

whe

n te

sted

163

Man

ufac

ture

r B1s

t Sta

ge14

War

m, D

amp

MS

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nD

ID N

OT

TES

T - C

ould

not

rem

ove

fittin

gs

164

Man

ufac

ture

r B1s

t Sta

ge42

War

m, D

amp

MS

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nD

ID N

OT

TES

T - C

ould

not

rem

ove

fittin

gs

167

Man

ufac

ture

r B1s

t Sta

ge2

War

m, D

amp

MS

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

OO

OO

OO

175

Man

ufac

ture

r B1s

t Sta

ge16

War

m, D

ryN

CS

ubur

ban

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

OO

OO

ΔO

Sta

rt-to

-dis

char

ge =

20.

29 p

si; 1

5 ps

i reg

ulat

or

177

Man

ufac

ture

r B1s

t Sta

ge8

War

m, D

ryN

CR

ural

Oth

erO

OO

OO

OO

183

Man

ufac

ture

r A1s

t Sta

ge11

War

m, D

amp

MS

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

OO

OO

OO

Inle

t thr

eads

bur

red;

cle

aned

and

con

tinue

d w

ith te

st18

4M

anuf

actu

rer A

1st S

tage

2W

arm

, Dam

pM

SR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OO

OO

OO

O18

7M

anuf

actu

rer A

1st S

tage

16W

arm

, Dam

pM

SR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OO

OO

OO

O18

9M

anuf

actu

rer A

1st S

tage

24W

arm

, Dam

pM

SR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OO

OA

djus

ting

sprin

g fro

zen;

Reg

ulat

or m

odel

doe

s no

t hav

e an

inte

gral

relie

f val

ve

192

Man

ufac

ture

r A1s

t Sta

ge13

War

m, D

amp

MS

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

ΔO

OO

OO

Stif

f adj

ustin

g sp

ring

195

Man

ufac

ture

r A1s

t Sta

ge14

War

m, D

amp

MS

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

OO

OO

OO

Inle

t fitt

ing

rust

y an

d di

fficu

lt to

rem

ove

219

Man

ufac

ture

r A1s

t Sta

ge10

War

m, D

amp

MS

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

OO

OO

OO

Mis

sing

pre

ssur

e ga

uge

plug

222

Man

ufac

ture

r A1s

t Sta

ge15

Coo

l, D

amp

MI

Rur

alE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

ΔO

OO

OO

OIn

let a

nd o

utle

t fitt

ings

rust

y an

d di

fficu

lt to

rem

ove

230

Man

ufac

ture

r A1s

t Sta

ge15

Coo

l, D

ryS

DR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OO

OO

OO

O24

4M

anuf

actu

rer A

1st S

tage

17C

ool,

Dry

SD

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

OO

OO

OO

247

Man

ufac

ture

r B1s

t Sta

ge8

Coo

l, D

ryS

DR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OO

OO

OO

XP

RD

rese

ated

at 1

2.67

psi

258

Man

ufac

ture

r B1s

t Sta

ge32

Coo

l, D

ryIA

Rur

alE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

OO

utle

t pre

ssur

e w

ould

not

sta

biliz

e du

ring

adju

stm

ent

264

Man

ufac

ture

r B1s

t Sta

ge16

Coo

l, D

ryN

CS

ubur

ban

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eD

ID N

OT

TES

T - L

eake

d th

roug

h sm

all h

ole

at th

e bo

ttom

of t

he re

gula

tor

267

Man

ufac

ture

r B1s

t Sta

ge41

Coo

l, D

ryIA

Rur

alE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

OO

utle

t pre

ssur

e w

ould

not

sta

biliz

e du

ring

adju

stm

ent

275

Man

ufac

ture

r A1s

t Sta

ge47

Coo

l, D

ryIA

Rur

alE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

OX

Leak

thro

ugh

regu

lato

r; st

oppe

d te

st a

t 27

psig

out

let p

ress

ure

280

Man

ufac

ture

r A1s

t Sta

ge46

Coo

l, D

ryIA

Rur

alE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

ΔΔ

OO

XR

egul

ator

is ru

sty;

slo

w lo

ck-u

p; le

aked

thro

ugh

regu

lato

r dur

ing

high

pre

ssur

e lo

ck-u

p te

st (2

50 p

sig)

281

Man

ufac

ture

r A1s

t Sta

ge31

Coo

l, D

ryIA

Rur

alE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

OO

OO

OR

egul

ator

mod

el d

oes

not h

ave

an in

tegr

al re

lief v

alve

290

Man

ufac

ture

r A1s

t Sta

ge11

Coo

l, D

ryS

DR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

ΔO

OO

OO

OP

ress

ure

relie

f scr

een

mis

sing

299

Man

ufac

ture

r A1s

t Sta

ge50

Coo

l, D

ryS

DR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OO

OO

OR

egul

ator

mod

el d

oes

not h

ave

an in

tegr

al re

lief v

alve

301

Man

ufac

ture

r A1s

t Sta

ge32

Coo

l, D

ryIA

Rur

alE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

OO

OO

OR

egul

ator

mod

el d

oes

not h

ave

an in

tegr

al re

lief v

alve

311

Man

ufac

ture

r A1s

t Sta

ge5

Coo

l, D

amp

MI

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

OO

OO

OO

Inle

t and

out

let f

ittin

gs ru

sty

and

diffi

cult

to re

mov

e

321

Man

ufac

ture

r B1s

t Sta

ge57

Coo

l, D

ryS

DE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

OLo

w o

utle

t pre

ssur

es e

ven

with

adj

ustm

ent a

ll th

e w

ay o

pen

324

Man

ufac

ture

r A1s

t Sta

ge16

Coo

l, D

amp

MI

OO

OO

OO

O32

6M

anuf

actu

rer A

1st S

tage

17C

ool,

Dry

SD

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

OO

OO

OO

332

Man

ufac

ture

r A1s

t Sta

ge24

War

m, D

ryM

SR

ural

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eX

Mis

sing

bon

net c

ap; r

egul

ator

per

form

ed w

ithin

UL

crite

ria w

hen

test

ed;

regu

lato

r mod

el d

oes

not h

ave

an in

tegr

al re

lief v

alve

338

Man

ufac

ture

r B1s

t Sta

ge8

Coo

l, D

amp

WA

Sub

urba

nTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

OO

OO

OO

341

Man

ufac

ture

r B1s

t Sta

ge5

Coo

l, D

amp

WA

Sub

urba

nTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

OO

OO

OO

344

Man

ufac

ture

r A1s

t Sta

ge22

War

m, D

ryK

YO

ther

OO

OA

djus

ting

scre

w b

acke

d al

l the

way

out

; Reg

ulat

or m

odel

doe

s no

t hav

e an

in

tegr

al re

lief v

alve

361

Man

ufac

ture

r B1s

t Sta

ge27

War

m, D

ryC

AU

rban

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

ΔΔ

OO

OX

XA

djus

ting

scre

w a

ll th

e w

ay d

own;

Low

relie

f and

rese

atin

g pr

essu

res

(10.

92

psi g

and

10.

71 p

sig,

resp

ectiv

ely)

416

Man

ufac

ture

r A1s

t Sta

ge7

War

m, D

ryV

AR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

ΔO

OO

OO

OIn

let a

nd o

utle

t fitt

ings

rust

y an

d di

fficu

lt to

rem

ove

417

Man

ufac

ture

r A1s

t Sta

ge10

War

m, D

ryV

AR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OO

OO

OO

OS

low

lock

-up

at h

igh

pres

sure

425

Man

ufac

ture

r A1s

t Sta

ge18

War

m, D

ryV

AR

ural

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

OO

OO

OO

431

Man

ufac

ture

r A1s

t Sta

ge43

Coo

l, D

ryS

DR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

DID

NO

T TE

ST

- Did

not

relie

ve th

roug

h th

e ve

nt; l

eake

d th

roug

h m

issi

ng

bod y

scr

ew

440

Man

ufac

ture

r B1s

t Sta

ge6

War

m, D

ryS

CR

ural

Oth

erO

OO

OO

OX

Low

rese

atin

g pr

essu

res

(13.

7 ps

i)44

1M

anuf

actu

rer A

1st S

tage

12W

arm

, Dry

SC

Urb

anE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

OO

OO

OO

O44

9M

anuf

actu

rer B

1st S

tage

7W

arm

, Dry

VA

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

OO

OX

Cha

tters

and

leak

s th

roug

h P

RD

dur

ing

high

pre

ssur

e lo

ck-u

p te

st (2

50 p

sig

inle

t )

450

Man

ufac

ture

r B1s

t Sta

ge7

War

m, D

amp

VA

Rur

alFa

ulty

regu

lato

rO

OO

OO

OO

460

Man

ufac

ture

r B1s

t Sta

ge41

War

m, D

ryV

AR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OO

utle

t pre

ssur

e w

ould

not

sta

biliz

e du

ring

adju

stm

ent;

adju

stin

g nu

t fro

zen

in

plac

e46

1M

anuf

actu

rer B

1st S

tage

46W

arm

, Dry

VA

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

XC

hatte

rs a

nd le

aks

thro

ugh

PR

D d

urin

g ad

just

men

t

468

Man

ufac

ture

r A1s

t Sta

ge18

Coo

l, D

ryW

IU

rban

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

OO

OO

OO

470

Man

ufac

ture

r A1s

t Sta

ge41

Coo

l, D

ryP

AS

ubur

ban

Oth

erO

OO

OO

Reg

ulat

or m

odel

doe

s no

t hav

e an

inte

gral

relie

f val

ve; c

ap c

over

ing

adju

stm

ent d

iffic

ult t

o re

mov

e47

2M

anuf

actu

rer B

1st S

tage

8W

arm

, Dry

NJ

Rur

alO

ther

: nee

ded

3/4"

out

let

OO

OO

OO

O47

4M

anuf

actu

rer B

1st S

tage

16W

arm

, Dry

NJ

Sub

urba

nE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

OO

OO

-R

egul

ator

mod

el d

oes

not h

ave

an in

tegr

al re

lief v

alve

; Max

lock

-up

= 16

.2 p

si

478

Man

ufac

ture

r A1s

t Sta

ge30

Coo

l, D

ryW

IR

ural

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

OO

OO

Reg

ulat

or m

odel

doe

s no

t hav

e an

inte

gral

relie

f val

ve48

4M

anuf

actu

rer A

1st S

tage

27C

ool,

Dam

pIN

Rur

alE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

OO

OO

OR

egul

ator

mod

el d

oes

not h

ave

an in

tegr

al re

lief v

alve

487

Man

ufac

ture

r A1s

t Sta

ge25

Coo

l, D

amp

INR

ural

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

Cou

ld n

ot a

djus

t reg

ulat

or; l

ocke

d in

pla

ce

488

Man

ufac

ture

r A1s

t Sta

ge43

Coo

l, D

amp

INR

ural

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

OO

OO

Reg

ulat

or m

odel

doe

s no

t hav

e an

inte

gral

relie

f val

ve48

9M

anuf

actu

rer A

1st S

tage

39C

ool,

Dam

pIN

Rur

alE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

OO

OO

OR

egul

ator

mod

el d

oes

not h

ave

an in

tegr

al re

lief v

alve

491

Man

ufac

ture

r B1s

t Sta

ge10

War

m, D

amp

FLS

ubur

ban

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

ΔO

OO

OO

OIn

let a

nd o

utle

t fitt

ings

diff

icul

t to

rem

ove;

bur

red

thre

ads

492

Man

ufac

ture

r B1s

t Sta

ge1

War

m, D

amp

FLS

ubur

ban

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OO

OO

OO

O49

3M

anuf

actu

rer B

1st S

tage

3W

arm

, Dam

pFL

Sub

urba

nFa

ulty

regu

lato

r: pa

int

ΔO

OO

OO

OV

ery

rust

y; d

id n

ot re

gula

te w

ell

507

Man

ufac

ture

r A1s

t Sta

ge45

Coo

l, D

ryIA

Urb

anE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

OO

OO

OR

egul

ator

mod

el d

oes

not h

ave

an in

tegr

al re

lief v

alve

509

Man

ufac

ture

r A1s

t Sta

ge6

War

m, D

amp

VA

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

OO

OO

OO

511

Man

ufac

ture

r A1s

t Sta

ge4

War

m, D

ryV

AR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OO

OO

OO

O53

8M

anuf

actu

rer A

1st S

tage

16W

arm

, Dry

PA

Sub

urba

nTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

O-

XS

tarte

d to

leak

thro

ugh

PR

V a

t 0 c

fh a

nd 2

5 ps

ig in

let;

Max

lock

-up

= 14

.97

psi.

544

Man

ufac

ture

r A1s

t Sta

ge42

Coo

l, D

amp

INR

ural

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

OO

OO

Reg

ulat

or m

odel

doe

s no

t hav

e an

inte

gral

relie

f val

ve

553

Man

ufac

ture

r A1s

t Sta

ge39

War

m, D

ryIN

Sub

urba

nE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

OO

OO

OR

egul

ator

mod

el d

oes

not h

ave

an in

tegr

al re

lief v

alve

554

Man

ufac

ture

r A1s

t Sta

ge48

Coo

l, D

amp

INR

ural

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

OO

OO

Reg

ulat

or m

odel

doe

s no

t hav

e an

inte

gral

relie

f val

ve55

7M

anuf

actu

rer A

1st S

tage

33C

ool,

Dam

pIN

Rur

alE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

OO

OO

OR

egul

ator

mod

el d

oes

not h

ave

an in

tegr

al re

lief v

alve

559

Man

ufac

ture

r B1s

t Sta

ge49

Coo

l, D

amp

INR

ural

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

OO

OO

utle

t pre

ssur

e w

ould

not

sta

biliz

e du

ring

lock

-up

test

ing

563

Man

ufac

ture

r A1s

t Sta

ge28

Coo

l, D

amp

INR

ural

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

Cou

ld n

ot a

djus

t reg

ulat

or; l

ocke

d in

pla

ce56

5M

anuf

actu

rer B

1st S

tage

16C

ool,

Dam

pM

IR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OO

OO

XC

hatte

rs a

nd le

aks

thro

ugh

regu

lato

r at 2

50 p

sig

inle

t pre

ssur

e an

d 80

cfh

571

Man

ufac

ture

r B1s

t Sta

ge10

Coo

l, D

amp

MI

Rur

alFa

ulty

regu

lato

rO

XLe

aked

thro

ugh

PR

D d

urin

g ad

just

men

t

572

Man

ufac

ture

r B1s

t Sta

ge10

Coo

l, D

amp

MI

Rur

alO

OO

OO

Reg

ulat

or m

odel

doe

s no

t hav

e an

inte

gral

relie

f val

ve

593

Man

ufac

ture

r A1s

t Sta

ge17

Coo

l, D

amp

ME

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

ΔO

-O

Slo

w lo

ck-u

p at

100

psi

g in

let p

ress

ure

614

Man

ufac

ture

r A1s

t Sta

ge22

Coo

l, D

ryIA

Rur

alE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

OO

OO

-R

egul

ator

mod

el d

oes

not h

ave

an in

tegr

al re

lief v

alve

; Max

lock

-up

= 17

.6 p

si

615

Man

ufac

ture

r B1s

t Sta

ge15

Coo

l, D

ryIA

Rur

alFa

ulty

regu

lato

rO

OO

OO

XLe

ak a

roun

d P

RD

flan

ge

617

Man

ufac

ture

r B1s

t Sta

ge10

Coo

l, D

ryIA

Rur

alFa

ulty

regu

lato

r: le

aked

OO

OO

OX

XLo

w re

lief a

nd re

seat

ing

pres

sure

s (1

3.97

psi

g an

d 13

.88

psig

, res

pect

ivel

y)

618

Man

ufac

ture

r B1s

t Sta

ge8

Coo

l, D

ryIA

Rur

alFa

ulty

regu

lato

r: ba

cked

ove

r und

ergr

ound

tank

with

pi

ckup

DID

NO

T TE

ST

- Lea

ked

thro

ugh

crim

p in

regu

lato

r bod

y at

250

psi

g an

d 80

cf

h

623

Man

ufac

ture

r B1s

t Sta

ge25

Coo

l, D

ryIA

Urb

anE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

OO

OO

OR

egul

ator

mod

el d

oes

not h

ave

an in

tegr

al re

lief v

alve

628

Man

ufac

ture

r B1s

t Sta

ge26

Coo

l, D

ryIA

Urb

anE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

OO

OO

OR

egul

ator

mod

el d

oes

not h

ave

an in

tegr

al re

lief v

alve

636

Man

ufac

ture

r A1s

t Sta

ge25

War

m, D

ryN

JS

ubur

ban

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eD

ID N

OT

TES

T - L

eake

d th

roug

h ar

ea w

here

the

top

and

botto

m o

f the

re

gula

tor a

re b

olte

d to

geth

er

656

Man

ufac

ture

r B1s

t Sta

ge4

Coo

l, D

ryN

YU

rban

Oth

er: r

eloc

ated

tank

, cha

nged

regs

OO

OO

OX

XLo

w re

lief a

nd re

seat

ing

pres

sure

s (1

0.9

psig

and

10.

8 ps

ig, r

espe

ctiv

ely)

657

Man

ufac

ture

r B1s

t Sta

ge4

Coo

l, D

ryN

YU

rban

Oth

er: r

eloc

ated

tank

OO

OO

OO

O69

7M

anuf

actu

rer B

1st S

tage

43C

ool,

Dry

SD

Rur

alE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

OO

OO

OR

egul

ator

mod

el d

oes

not h

ave

an in

tegr

al re

lief v

alve

718

Man

ufac

ture

r A1s

t Sta

ge27

Coo

l, D

ryIA

Rur

alE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

OO

XC

hatte

rs a

nd le

aks

thro

ugh

PR

D a

t 80

cfh

and

100

psig

inle

t pre

ssur

e

733

Man

ufac

ture

r A1s

t Sta

ge27

Coo

l, D

ryIA

Rur

alE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

OO

OO

OR

egul

ator

mod

el d

oes

not h

ave

an in

tegr

al re

lief v

alve

757

Man

ufac

ture

r B1s

t Sta

ge27

Coo

l, D

ryIA

Rur

alE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

OO

OO

OR

egul

ator

mod

el d

oes

not h

ave

an in

tegr

al re

lief v

alve

760

Man

ufac

ture

r B1s

t Sta

ge40

Coo

l, D

ryS

DR

ural

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eD

ID N

OT

TES

T - C

ould

not

rem

ove

fittin

gs

778

Man

ufac

ture

r A1s

t Sta

ge11

Coo

l, D

amp

AK

Rur

alE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

OO

OO

OO

O78

3M

anuf

actu

rer B

1st S

tage

14W

arm

, Dam

pM

SFa

ulty

regu

lato

rO

Out

let p

ress

ure

wou

ld n

ot s

tabi

lize;

pre

ssur

e co

ntin

ued

to c

limb

at 1

00 p

sig

inle

t pre

ssur

e an

d 80

cfh

O Δ X O Δ X O + - X O Δ X * **Th

e ty

pe o

f reg

ulat

or m

arke

d is

inco

nsis

tent

with

the

reas

on fo

r rem

oval

Can

not s

et in

itial

pre

ssur

e du

ring

regu

lato

r adj

ustm

ent;

pres

sure

fluc

tuat

es a

nd/o

r nev

er re

ache

s se

tpoi

nt

Reg

ulat

or d

id n

ot m

eet U

L 14

4 pr

essu

re re

lief s

tart-

to d

isch

arge

and

/or r

esea

ting

crite

ria fo

r a n

ew re

gula

tor i

n 1

out o

f 3 tr

ials

(usu

ally

occ

urre

d on

the

first

tria

l)

Reg

ulat

or d

id n

ot m

eet U

L 14

4 pr

essu

re re

lief s

tart-

to d

isch

arge

and

/or r

esea

ting

crite

ria fo

r a n

ew re

gula

tor i

n 2

or 3

tria

ls o

ut o

f 3.

Rea

son

for r

egul

ator

rem

oval

mar

ked

is in

cons

iste

nt w

ith th

e m

anuf

actu

rer's

dat

e st

amp

Pres

sure

relie

f dev

ice

did

not v

ent

Reg

ulat

or m

issi

ng e

ssen

tial c

ompo

nent

s (b

onne

t cap

; out

er s

crew

s, e

tc.)

Reg

ulat

or s

how

s si

gns

of c

orro

sion

, wea

r, et

c. b

ut s

till t

este

d

GEN

ERA

L

LOC

K-U

PR

egul

ator

mee

ts lo

ck-u

p cr

iteria

for a

new

regu

lato

r as

spec

ified

in U

L 14

4

Reg

ulat

or d

id n

ot m

eet U

L 14

4 lo

ck-u

p cr

iteria

for a

new

regu

lato

r in

1 ou

t of 3

tria

ls b

ut lo

cked

-up

low

er th

an th

e pr

essu

re re

lief s

tart-

to-d

isch

arge

(UL

144

< Lo

ck-u

p <

PRD

std

)

Reg

ulat

or d

id n

ot m

eet U

L 14

4 lo

ck-u

p cr

iteria

for a

new

regu

lato

r in

3 ou

t of 3

tria

ls b

ut lo

cked

-up

low

er th

an th

e pr

essu

re re

lief s

tart-

to-d

isch

arge

(UL

144

< Lo

ck-u

p <

PRD

std

)

Reg

ulat

or le

aked

thro

ugh

PR

D d

urin

g lo

ck-u

p te

stin

g (P

RD

std

< L

ock-

up)

Reg

ulat

or d

id n

ot m

eet U

L 14

4 lo

ck-u

p cr

iteria

for a

new

regu

lato

r in

2 ou

t of 3

tria

ls b

ut lo

cked

-up

low

er th

an th

e pr

essu

re re

lief s

tart-

to-d

isch

arge

(UL

144

< Lo

ck-u

p <

PRD

std

)

Reg

ulat

or in

goo

d co

nditi

on; n

o vi

sibl

e si

gn o

f a p

robl

em

Test

s no

t con

duct

ed

KEY

EXTE

RN

AL IN

SPEC

TIO

N

PRES

SUR

E R

ELIE

FR

egul

ator

mee

ts p

ress

ure

relie

f sta

rt-to

-dis

char

ge a

nd re

seat

ing

crite

ria fo

r a n

ew re

gula

tor a

s sp

ecifi

ed in

UL

144

Reg

ulat

or le

aked

thro

ugh

PR

D d

urin

g ad

just

men

t

INTE

RN

AL

AD

JUST

MEN

TR

egul

ator

in g

ood

cond

ition

; no

visi

ble

sign

of a

pro

blem

Reg

ulat

or s

how

s si

gns

of c

orro

sion

, wea

r, st

iff/fr

ozen

spr

ings

, slo

w to

reac

h se

tpoi

nt, e

tc. b

ut s

till t

este

d

REA

SON

FO

R F

AIL

UR

E

1ST

STAG

E R

EGU

LATO

RS

INSP

ECTI

ON

SR

EGU

LATO

R IN

FOR

MAT

ION

PRES

SUR

E R

ELIE

FLO

CK

-UP

Page 58: Performance, Durability, and Service Life of Low Pressure ... · Performance, Durability, and Service Life of vii September 2006 Low Pressure Propane Vapor Regulators Battelle Of

Performance, Durability, and Service Life of 40 September 2006 Low Pressure Propane Vapor Regulators Battelle

Tab

le 4

. Ove

rvie

w o

f sec

ond-

stag

e re

gula

tor

perf

orm

ance

.

Reg

ulat

or ID

Reg

ulat

or

Man

ufac

ture

r:R

egul

ator

Ty

peR

egul

ator

Ag

e (y

ears

)C

limat

eR

egul

ator

Lo

catio

n St

ate

Serv

ice

Area

Rea

son

for R

egul

ator

Rem

oval

Exte

rnal

Vi

sual

In

spec

tion

Inte

rnal

In

spec

tion

and

Adju

stm

ent

Mod

erat

e In

let

Pres

sure

Low

Inle

t Pr

essu

reH

igh

Inle

t Pr

essu

re

Star

t-to-

Dis

char

ge

Pres

sure

Res

eatin

g Pr

essu

re

2M

anuf

actu

rer A

2nd

Sta

ge4

Coo

l, D

amp

ME

Rur

alFa

ulty

regu

lato

rO

OO

OO

OO

5M

anuf

actu

rer A

2nd

Sta

ge4

Coo

l, D

amp

NH

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

OO

OO

OO

6M

anuf

actu

rer A

2nd

Sta

ge1

Coo

l, D

amp

NH

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

OO

OO

OO

20M

anuf

actu

rer A

2nd

Sta

ge11

Coo

l, D

ryS

DR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

DID

NO

T TE

ST

- Ven

t mis

sin g

out

er s

cree

n &

adj

ustin

g sc

rew

is b

ent

21M

anuf

actu

rer A

2nd

Sta

ge38

*W

arm

, Dam

pM

OR

ural

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

OO

OO

OO

22M

anuf

actu

rer B

2nd

Sta

ge41

War

m, D

amp

MO

Rur

alFa

ulty

regu

lato

rO

ΔX

Leak

thro

ugh

regu

lato

r at 1

0 ps

ig in

let p

ress

ure

and

0 cf

h (lo

ck-u

p)30

Man

ufac

ture

r B2n

d S

tage

15C

ool,

Dry

IAR

ural

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

OO

OO

XO

Max

sta

rt-to

-dis

char

ge p

ress

ure

= 36

.3" W

.C.

33M

anuf

actu

rer B

2nd

Sta

ge15

Coo

l, D

ryIA

Urb

anE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

OA

djus

tmen

t all

the

way

dow

n; lo

w o

utle

t pre

ssur

e (8

.6" W

.C.)

34M

anuf

actu

rer B

2nd

Sta

ge11

*C

ool,

Dry

IAU

rban

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

OO

OO

OO

Out

let f

ittin

g ru

sty

and

diffi

cult

to re

mov

e42

Man

ufac

ture

r B2n

d S

tage

16W

arm

, Dry

ILS

ubur

ban

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

Δ-

--

OO

Max

Loc

k-up

= 2

1.8"

W.C

.; sl

ow lo

ck-u

p47

Man

ufac

ture

r A2n

d S

tage

?C

ool,

Dry

SD

Rur

alO

Δ-

-O

OO

Max

Loc

k-up

= 1

4.81

" W.C

.; re

gula

tor c

hatte

rs48

Man

ufac

ture

r B2n

d S

tage

3C

ool,

Dam

pW

AR

ural

Faul

ty re

gula

tor

OX

Leak

ed th

roug

h P

RD

dur

ing

adju

stm

ent

49M

anuf

actu

rer B

2nd

Sta

ge8

Coo

l, D

amp

WA

Rur

alFa

ulty

regu

lato

rD

ID N

OT

TES

T - C

ould

not

rem

ove

inle

t fitt

ing

51M

anuf

actu

rer B

2nd

Sta

ge11

Coo

l, D

amp

WA

Sub

urba

nFa

ulty

regu

lato

rO

OO

OO

OO

52M

anuf

actu

rer B

2nd

Sta

ge10

Coo

l, D

amp

WA

Sub

urba

nFa

ulty

regu

lato

rO

ΔX

Leak

ed th

roug

h re

gula

tor a

t 10

psig

inle

t and

0.5

cfh

60M

anuf

actu

rer A

2nd

Sta

ge37

War

m, D

ryM

SR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OO

OO

OX

OM

ax s

tart-

to-d

isch

arge

pre

ssur

e =

34.5

" W.C

.65

Man

ufac

ture

r B2n

d S

tage

16C

ool,

Dam

pO

HR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OO

OO

OO

O68

Man

ufac

ture

r B2n

d S

tage

13C

ool,

Dam

pO

HS

ubur

ban

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OO

OO

XO

Max

Loc

k-up

= 1

3.5"

W.C

.; M

ax s

tart-

to-d

isch

arge

pre

ssur

e =

47.2

" W.C

.71

Man

ufac

ture

r A2n

d S

tage

2C

ool,

Dry

CO

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

XB

ad le

ak th

roug

h ad

just

ing

scre

w72

Man

ufac

ture

r A2n

d S

tage

16C

ool,

Dry

CO

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

XC

hatte

rs a

nd le

aks

thro

ugh

PR

D a

t 30

cfh

and

10 p

sig

inle

t90

Man

ufac

ture

r B2n

d S

tage

46C

ool,

Dry

SD

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

Δ-

--

OO

Max

Loc

k-up

= 1

8.1"

W.C

.

100

Man

ufac

ture

r D2n

d S

tage

44C

ool,

Dry

PA

Sub

urba

nO

ther

: ser

vice

wor

k at

cus

tom

er lo

catio

n &

foun

d ol

d re

gula

tor

ΔO

-O

OO

OV

ery

rust

y; M

ax L

ock-

up =

13.

8" W

.C.

113

Man

ufac

ture

r A2n

d S

tage

13C

ool,

Dry

NH

Rur

alO

ther

OO

OO

OM

ax s

tart-

to-d

isch

arge

= 3

3.15

" W.C

.11

7M

anuf

actu

rer A

2nd

Sta

ge9

War

m, D

ryO

HR

ural

OX

Leak

s th

roug

h P

RD

at 3

0 cf

h an

d 10

psi

g in

let

118

Man

ufac

ture

r A2n

d S

tage

8C

ool,

Dry

INR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OO

OO

OO

O11

9M

anuf

actu

rer A

2nd

Sta

ge9

Coo

l, D

ryO

HR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OO

OO

OO

O12

3M

anuf

actu

rer A

2nd

Sta

ge14

War

m, D

amp

NC

Sub

urba

nE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

OO

OO

OO

O12

4M

anuf

actu

rer A

2nd

Sta

ge16

War

m, D

amp

NC

Rur

alE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

XLe

ak th

roug

h re

gula

tor a

t 10

psig

inle

t and

0 c

fh (l

ock-

up)

128

Man

ufac

ture

r B2n

d S

tage

16W

arm

, Dam

pN

CR

ural

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eD

ID N

OT

TES

T - C

rack

ed re

gula

tor b

ody

130

Man

ufac

ture

r B2n

d S

tage

17W

arm

, Dam

pN

CS

ubur

ban

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

ΔO

OO

XO

Max

sta

rt-to

-dic

harg

e pr

essu

re =

34.

4" W

.C.

136

Man

ufac

ture

r B2n

d S

tage

35C

ool,

Dry

IAR

ural

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eD

ID N

OT

TES

T - C

ould

not

rem

ove

outle

t fitt

ing

155

Man

ufac

ture

r A2n

d S

tage

4W

arm

, Dam

pM

SR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

ΔO

OO

OO

OP

ress

ure

relie

f scr

een

mis

sing

156

Man

ufac

ture

r A2n

d S

tage

11W

arm

, Dam

pM

SR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OO

OO

OO

O16

8M

anuf

actu

rer A

2nd

Sta

ge10

War

m, D

amp

MS

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

XLe

aks

thro

ugh

PR

D a

t 30

cfh

and

10 p

sig

inle

t; ve

nt s

cree

n m

issi

ng

170

Man

ufac

ture

r A2n

d S

tage

22W

arm

, Dry

KY

Sub

urba

nE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

ΔO

OO

OX

OIn

let f

ittin

g ru

sty

and

diffi

cult

to re

mov

e; M

ax s

tart-

to-d

icha

rge

pres

sure

= 3

5.5"

W

.C.

171

Man

ufac

ture

r B2n

d S

tage

14W

arm

, Dry

INS

ubur

ban

Oth

erO

OO

OO

OO

174

Man

ufac

ture

r B2n

d S

tage

14W

arm

, Dry

KY

Rur

alΔ

OO

OO

OO

Pre

ssur

e re

lief s

cree

n m

issi

ng

176

Man

ufac

ture

r B2n

d S

tage

16W

arm

, Dry

NC

Rur

alE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

ΔO

OO

OO

OP

ress

ure

relie

f scr

een

rust

y17

9M

anuf

actu

rer A

2nd

Sta

ge15

War

m, D

ryN

CR

ural

Oth

erO

OO

OO

OO

180

Man

ufac

ture

r A2n

d S

tage

8W

arm

, Dam

pM

SR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

XB

onne

t cap

mis

sing

; reg

ulat

or p

erfo

rmed

with

in U

L cr

iteria

whe

n te

sted

191

Man

ufac

ture

r B2n

d S

tage

48W

arm

, Dam

pM

SR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OX

Leak

ed th

roug

h P

RD

dur

ing

adju

stm

ent

207

Man

ufac

ture

r A2n

d S

tage

34C

ool,

Dam

pM

ER

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OO

OO

OM

ax s

tart-

to-d

isch

arge

= 3

5.9"

W.C

.20

8M

anuf

actu

rer B

2nd

Sta

ge47

Coo

l, D

amp

ME

Urb

anTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nD

ID N

OT

TES

T - F

lare

d ou

tlet;

Did

not

hav

e pr

oper

fitti

ngs

221

Man

ufac

ture

r A2n

d S

tage

15C

ool,

Dam

pM

IR

ural

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

OO

OO

XO

Inle

t fitt

ing

rust

y an

d di

fficu

lt to

rem

ove;

Max

sta

rt-to

-dic

harg

e pr

essu

re =

35.

6"

W.C

.22

3M

anuf

actu

rer A

2nd

Sta

ge14

Coo

l, D

amp

MI

Rur

alE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

ΔO

OO

OO

OIn

let f

ittin

g ru

sty

and

diffi

cult

to re

mov

e22

8M

anuf

actu

rer B

2nd

Sta

ge47

Coo

l, D

ryS

DR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OO

--

OM

ax L

ock-

up =

14.

2" W

.C.;

Max

sta

rt-to

-dis

char

ge =

33.

6" W

.C.

255

Man

ufac

ture

r B2n

d S

tage

32C

ool,

Dry

IAR

ural

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

OO

OO

XO

Max

sta

rt-to

-dis

char

ge p

ress

ure

= 60

.1" W

.C. d

urin

g th

e tri

al 1

256

Man

ufac

ture

r B2n

d S

tage

40C

ool,

Dry

IAR

ural

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

ΔX

Dirt

y in

side

regu

lato

r; Le

ak th

roug

h re

gula

tor a

t 10

psig

inle

t and

0 c

fh; M

ax

Lock

-up

= 15

.7" W

.C.

257

Man

ufac

ture

r B2n

d S

tage

36C

ool,

Dry

IAR

ural

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

O-

-O

OO

Max

Loc

k-up

= 1

6.6"

W.C

.26

2M

anuf

actu

rer A

2nd

Sta

ge39

Coo

l, D

ryIA

Rur

alE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

OO

OO

OO

O26

3M

anuf

actu

rer A

2nd

Sta

ge41

Coo

l, D

ryIA

Rur

alE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

OO

OO

OX

OM

ax s

tart-

to-d

isch

arge

pre

ssur

e =

33.5

" W.C

.26

8M

anuf

actu

rer A

2nd

Sta

ge32

Coo

l, D

ryIA

Rur

alE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

ΔO

OO

OX

OR

egul

ator

bol

ts v

ery

rust

y; M

ax s

tart-

to-d

icha

rge

pres

sure

= 4

2.6"

W.C

.26

9M

anuf

actu

rer B

2nd

Sta

ge16

Coo

l, D

ryIA

Rur

alE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

ΔO

OO

OO

OIn

let a

nd o

utle

t fitt

ings

diff

icul

t to

rem

ove;

man

y co

ats

of p

aint

282

Man

ufac

ture

r B2n

d S

tage

42*

Coo

l, D

ryIA

Rur

alE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

OO

OO

OO

O29

6M

anuf

actu

rer A

2nd

Sta

ge9

Coo

l, D

ryS

DR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

ΔO

OO

OO

OP

ress

ure

relie

f scr

een

mis

sing

312

Man

ufac

ture

r A2n

d S

tage

8C

ool,

Dam

pM

IR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OO

OO

OO

O32

7M

anuf

actu

rer A

2nd

Sta

ge18

Coo

l, D

ryS

DR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OO

OO

OO

O34

3M

anuf

actu

rer A

2nd

Sta

ge2

War

m, D

ryK

YR

ural

Oth

erD

ID N

OT

TES

T - C

ould

not

rem

ove

inle

t fitt

ing

345

Man

ufac

ture

r A2n

d S

tage

4W

arm

, Dry

KY

Rur

alO

ther

OO

-+

OX

OM

ax L

ock-

up =

13.

9" W

.C.;

Max

sta

rt-to

-dis

char

ge p

ress

ure

= 41

.8" W

.C.

367

Man

ufac

ture

r B2n

d S

tage

39W

arm

, Dam

pW

AU

rban

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OO

OO

OX

OM

ax s

tart-

to-d

isch

arge

pre

ssur

e =

59" W

.C.

379

Man

ufac

ture

r A2n

d S

tage

47C

ool,

Dry

SD

Rur

alO

OO

OO

OO

415

Man

ufac

ture

r A2n

d S

tage

7W

arm

, Dry

VA

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

OO

OO

OO

444

Man

ufac

ture

r A2n

d S

tage

6W

arm

, Dam

pS

CS

ubur

ban

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OO

OO

OO

O44

5M

anuf

actu

rer B

2nd

Sta

ge6

War

m, D

ryS

CR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OO

OO

OX

OM

ax s

tart-

to-d

isch

arge

pre

ssur

e =

34" W

.C.

446

Man

ufac

ture

r B2n

d S

tage

6W

arm

, Dry

SC

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

OO

OO

OO

462

Man

ufac

ture

r B2n

d S

tage

**7

War

m, D

ryV

AR

ural

Cha

nged

from

sin

gle

to d

ual r

egul

ator

sys

tem

OO

OO

OO

O46

5M

anuf

actu

rer B

2nd

Sta

ge25

Coo

l, D

ryS

DR

ural

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

OO

OO

OO

469

Man

ufac

ture

r A2n

d S

tage

41C

ool,

Dry

WI

Urb

anE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

OO

OO

OM

ax s

tart-

to-d

isch

arge

= 3

5.7"

W.C

. dur

ing

trial

147

9M

anuf

actu

rer A

2nd

Sta

ge30

Coo

l, D

ryW

IR

ural

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

XR

egul

ator

cha

tters

and

leak

s th

roug

h P

RD

at 3

0 cf

h an

d 10

psi

g in

let

482

Man

ufac

ture

r A2n

d S

tage

25C

ool,

Dam

pIN

Rur

alE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

DID

NO

T TE

ST

- Adj

ustin

g pl

ate

jam

med

into

the

botto

m o

f the

regu

lato

r

483

Man

ufac

ture

r A2n

d S

tage

25C

ool,

Dam

pIN

Rur

alE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

OO

OO

OM

ax s

tart-

to-d

isch

arge

= 3

5" W

.C.

502

Man

ufac

ture

r B2n

d S

tage

20C

ool,

Dry

IAR

ural

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

OO

OO

XO

Max

sta

rt-to

-dis

char

ge p

ress

ure

= 35

.2" W

.C.

505

Man

ufac

ture

r B2n

d S

tage

25C

ool,

Dry

IAR

ural

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

OO

OO

OO

512

Man

ufac

ture

r A2n

d S

tage

4W

arm

, Dry

VA

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

OO

OO

OO

514

Man

ufac

ture

r A2n

d S

tage

11W

arm

, Dam

pV

AR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OO

OO

OO

XLo

w re

seat

ing

pres

sure

s (1

1.8"

W.C

.)52

0M

anuf

actu

rer B

2nd

Sta

ge26

Coo

l, D

amp

PA

Sub

urba

nE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

OO

OO

OO

O52

2M

anuf

actu

rer A

2nd

Sta

ge31

Coo

l, D

amp

PA

Sub

urba

nE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

DID

NO

T TE

ST

- Adj

ustin

g pl

ate

and

sprin

g m

issi

ng fr

om re

gula

tor

524

Man

ufac

ture

r B2n

d S

tage

31C

ool,

Dam

pP

AS

ubur

ban

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

OO

OO

ΔO

Max

sta

rt-to

-dis

char

ge =

33.

4" W

.C.

525

Man

ufac

ture

r B2n

d S

tage

25C

ool,

Dam

pP

AS

ubur

ban

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

OO

OO

OO

527

Man

ufac

ture

r B2n

d S

tage

31C

ool,

Dam

pP

AS

ubur

ban

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

OO

OO

OO

530

Man

ufac

ture

r B2n

d S

tage

25C

ool,

Dam

pP

AS

ubur

ban

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

OO

OO

XO

Max

sta

rt-to

-dis

char

ge p

ress

ure

= 34

.2" W

.C.

531

Man

ufac

ture

r B2n

d S

tage

32C

ool,

Dam

pP

AS

ubur

ban

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

OO

OO

OO

533

Man

ufac

ture

r A2n

d S

tage

26C

ool,

Dam

pP

AS

ubur

ban

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

OO

OO

OO

534

Man

ufac

ture

r A2n

d S

tage

25C

ool,

Dam

pP

AS

ubur

ban

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

OO

OO

OM

ax L

ock-

up =

13.

5" W

.C.

546

Man

ufac

ture

r A2n

d S

tage

27W

arm

, Dry

INS

ubur

ban

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eD

ID N

OT

TES

T - C

ould

not

rem

ove

inle

t fitt

ing

550

Man

ufac

ture

r B2n

d S

tage

22C

ool,

Dam

pIN

Rur

alE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

OO

OX

OV

ery

rust

y; M

ax s

tart-

to-d

isch

arge

pre

ssur

e =

35.7

" W.C

.55

6M

anuf

actu

rer A

2nd

Sta

ge34

Coo

l, D

amp

INR

ural

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

OO

OO

XO

Max

sta

rt-to

-dis

char

ge p

ress

ure

= 44

.5" W

.C.

566

Man

ufac

ture

r B2n

d S

tage

16C

ool,

Dam

pM

IR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OO

OO

OO

O56

9M

anuf

actu

rer B

2nd

Sta

ge17

Coo

l, D

amp

MI

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

OO

OO

OO

573

Man

ufac

ture

r B2n

d S

tage

10C

ool,

Dam

pM

IR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OO

OO

OO

O63

4M

anuf

actu

rer A

2nd

Sta

ge25

War

m, D

ryN

JS

ubur

ban

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

OO

OO

ΔO

Max

sta

rt-to

-dis

char

ge =

35"

W.C

.64

4M

anuf

actu

rer B

2nd

Sta

ge13

Coo

l, D

ryN

YS

ubur

ban

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OO

OO

OO

O65

3M

anuf

actu

rer B

2nd

Sta

ge7

Coo

l, D

ryN

YR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OO

OO

OO

O65

5M

anuf

actu

rer B

2nd

Sta

ge7

Coo

l, D

ryN

YU

rban

Oth

er: r

ed ta

g po

olO

OO

OO

OO

670

Man

ufac

ture

r B2n

d S

tage

33W

arm

, Dam

pFL

Sub

urba

nO

ther

: ow

ner d

ied,

sys

tem

upg

rade

for n

ew c

lient

OX

Ver

y ru

sty

inte

rior;

adju

stin

g sc

rew

froz

en in

pla

ce67

1M

anuf

actu

rer B

2nd

Sta

ge33

War

m, D

amp

FLS

ubur

ban

Oth

er: s

yste

m u

pgra

de- n

ew o

wne

r mov

ed in

DID

NO

T TE

ST

- Ad j

ustin

g pl

ate

rust

ed in

pla

ce a

nd b

roke

n68

4M

anuf

actu

rer A

2nd

Sta

ge12

War

m, D

amp

WA

Rur

alO

OO

OO

OO

691

Man

ufac

ture

r B2n

d S

tage

27C

ool,

Dry

SD

Urb

anE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

OO

OO

OM

ax s

tart-

to-d

isch

arge

= 3

5.2"

W.C

.

693

Man

ufac

ture

r B2n

d S

tage

8C

ool,

Dry

SD

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

OO

OO

Low

rese

atin

g pr

essu

res

(17.

6" W

.C.)

711

Man

ufac

ture

r A2n

d S

tage

27C

ool,

Dry

SD

Rur

alE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

OO

OO

OX

PR

D d

id n

ot re

lieve

eve

n af

ter i

ncre

asin

g pr

essu

re to

65"

W.C

.

767

Man

ufac

ture

r B2n

d S

tage

28C

ool,

Dry

IAU

rban

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

ΔO

OO

OO

Mis

sing

scr

een

over

PR

D; v

ery

oily

insi

de a

nd o

utsi

de

776

Man

ufac

ture

r B2n

d S

tage

19W

arm

, Dam

pM

SO

OO

OO

OO

O Δ X O Δ X O + - X O Δ X * **Th

e ty

pe o

f reg

ulat

or m

arke

d is

inco

nsis

tent

with

the

reas

on fo

r rem

oval

Can

not s

et in

itial

pre

ssur

e du

ring

regu

lato

r adj

ustm

ent;

pres

sure

fluc

tuat

es a

nd/o

r nev

er re

ache

s se

tpoi

nt

Reg

ulat

or d

id n

ot m

eet U

L 14

4 pr

essu

re re

lief s

tart-

to d

isch

arge

and

/or r

esea

ting

crite

ria fo

r a n

ew re

gula

tor i

n 1

out o

f 3 tr

ials

(usu

ally

occ

urre

d on

the

first

tria

l)

Reg

ulat

or d

id n

ot m

eet U

L 14

4 pr

essu

re re

lief s

tart-

to d

isch

arge

and

/or r

esea

ting

crite

ria fo

r a n

ew re

gula

tor i

n 2

or 3

tria

ls o

ut o

f 3.

Rea

son

for r

egul

ator

rem

oval

mar

ked

is in

cons

iste

nt w

ith th

e m

anuf

actu

rer's

dat

e st

amp

Pres

sure

relie

f dev

ice

did

not v

ent

Reg

ulat

or m

issi

ng e

ssen

tial c

ompo

nent

s (b

onne

t cap

; out

er s

crew

s, e

tc.)

Reg

ulat

or s

how

s si

gns

of c

orro

sion

, wea

r, et

c. b

ut s

till t

este

d

GEN

ERAL

LOC

K-U

PR

egul

ator

mee

ts lo

ck-u

p cr

iteria

for a

new

regu

lato

r as

spec

ified

in U

L 14

4

Reg

ulat

or d

id n

ot m

eet U

L 14

4 lo

ck-u

p cr

iteria

for a

new

regu

lato

r in

1 ou

t of 3

tria

ls b

ut lo

cked

-up

low

er th

an th

e pr

essu

re re

lief s

tart-

to-d

isch

arge

(UL

144

< Lo

ck-u

p <

PR

D s

td)

Reg

ulat

or d

id n

ot m

eet U

L 14

4 lo

ck-u

p cr

iteria

for a

new

regu

lato

r in

3 ou

t of 3

tria

ls b

ut lo

cked

-up

low

er th

an th

e pr

essu

re re

lief s

tart-

to-d

isch

arge

(UL

144

< Lo

ck-u

p <

PR

D s

td)

Reg

ulat

or le

aked

thro

ugh

PRD

dur

ing

lock

-up

test

ing

(PR

D s

td <

Loc

k-up

)

Reg

ulat

or d

id n

ot m

eet U

L 14

4 lo

ck-u

p cr

iteria

for a

new

regu

lato

r in

2 ou

t of 3

tria

ls b

ut lo

cked

-up

low

er th

an th

e pr

essu

re re

lief s

tart-

to-d

isch

arge

(UL

144

< Lo

ck-u

p <

PR

D s

td)

Reg

ulat

or in

goo

d co

nditi

on; n

o vi

sibl

e si

gn o

f a p

robl

em

Test

s no

t con

duct

ed

KEY

EXTE

RN

AL

INSP

ECTI

ON

PRES

SUR

E R

ELIE

FR

egul

ator

mee

ts p

ress

ure

relie

f sta

rt-to

-dis

char

ge a

nd re

seat

ing

crite

ria fo

r a n

ew re

gula

tor a

s sp

ecifi

ed in

UL

144

Reg

ulat

or le

aked

thro

ugh

PRD

dur

ing

adju

stm

ent

INTE

RN

AL

AD

JUST

MEN

TR

egul

ator

in g

ood

cond

ition

; no

visi

ble

sign

of a

pro

blem

Reg

ulat

or s

how

s si

gns

of c

orro

sion

, wea

r, st

iff/fr

ozen

spr

ings

, slo

w to

reac

h se

tpoi

nt, e

tc. b

ut s

till t

este

d

REA

SON

FO

R F

AILU

RE

2ND

STA

GE

REG

ULA

TOR

S

INSP

ECTI

ON

SR

EGU

LATO

R IN

FOR

MA

TIO

NPR

ESSU

RE

REL

IEF

LOC

K-U

P

Page 59: Performance, Durability, and Service Life of Low Pressure ... · Performance, Durability, and Service Life of vii September 2006 Low Pressure Propane Vapor Regulators Battelle Of

Performance, Durability, and Service Life of 41 September 2006 Low Pressure Propane Vapor Regulators Battelle

Reg

ulat

or ID

Reg

ulat

or

Man

ufac

ture

r:R

egul

ator

Ty

peR

egul

ator

Ag

e (y

ears

)C

limat

eR

egul

ator

Lo

catio

n St

ate

Serv

ice

Area

Rea

son

for R

egul

ator

Rem

oval

Exte

rnal

Vi

sual

In

spec

tion

Inte

rnal

In

spec

tion

and

Adju

stm

ent

Mod

erat

e In

let

Pres

sure

Low

Inle

t Pr

essu

reH

igh

Inle

t Pr

essu

re

Star

t-to-

Dis

char

ge

Pres

sure

Res

eatin

g Pr

essu

re

38M

anuf

actu

rer A

Sin

gle

37C

ool,

Dry

IAR

ural

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

Adj

ustin

g sp

ring

froze

n; lo

w o

utle

t pre

ssur

es

55M

anuf

actu

rer A

Sin

gle

15W

arm

, Dry

KSR

ural

Cha

nged

from

sin

gle

to d

ual r

egul

ator

sys

tem

OX

Leak

s th

roug

h P

RD

at 3

0 cf

h an

d 10

0 ps

ig in

let

67M

anuf

actu

rer A

Sin

gle

27C

ool,

Dam

pO

HR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OO

OO

OX

OM

ax s

tart-

to-d

isch

arge

= 3

5.4"

W.C

.

81M

anuf

actu

rer A

Sin

gle

13C

ool,

Dry

SDR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

XR

egul

ator

cha

tters

; lea

ks th

roug

h P

RD

at h

igh

flow

rate

s; s

-t-d

= 10

.2" W

.C.

85M

anuf

actu

rer A

Sin

gle

20C

ool,

Dry

SDR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

XO

XLe

ak th

roug

h re

gula

tor;

Max

Loc

k-up

= 1

7.8"

W.C

.; le

aks

thro

ugh

PR

D a

t hig

h flo

w ra

te (8

0 cf

h); s

-t-d

= 13

.7" W

.C.

91M

anuf

actu

rer A

Sin

gle

16C

ool,

Dry

SDR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OO

OS

tiff a

djus

ting

sprin

g; M

ax s

tart-

to-d

isch

arge

= 3

3.5"

W.C

.

92M

anuf

actu

rer A

Sin

gle

16C

ool,

Dry

SDR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OO

-O

OO

OM

ax L

ock-

up =

13.

6" W

.C.

97M

anuf

actu

rer A

Sin

gle

11C

ool,

Dry

SDR

ural

OO

O+

+O

OM

ax L

ock-

up =

17.

8" W

.C.

98M

anuf

actu

rer A

Sin

gle

18C

ool,

Dry

SDR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

XM

issi

ng b

onne

t cap

; max

imum

lock

-up

14" W

.C. d

urin

g th

e 10

0 ps

ig in

let t

est;

all o

ther

test

s pe

rform

ed w

ithin

the

UL

crite

ria

150

Man

ufac

ture

r AS

ingl

e13

War

m, D

ryM

SR

ural

Cha

nged

from

sin

gle

to d

ual r

egul

ator

sys

tem

OO

-O

OO

Max

Loc

k-up

= 1

7.8"

W.C

.

181

Man

ufac

ture

r AS

ingl

e23

War

m, D

amp

MS

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

Cou

ld n

ot a

djus

t reg

ulat

or d

own

to 1

1" W

.C.

182

Man

ufac

ture

r BS

ingl

e19

War

m, D

amp

MS

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

Δ-

-O

OR

usty

; Inl

et fi

tting

diff

icul

t to

rem

ove;

Max

Loc

k-up

= 2

1.6"

W.C

.

188

Man

ufac

ture

r AS

ingl

e54

War

m, D

amp

MS

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nX

Mis

sing

bon

net c

ap; m

axim

um lo

ck-u

p 29

.5" W

.C.;

lock

-up

high

er th

an U

L cr

iteria

at a

ll 3

inle

t pre

ssur

es; P

RD

s-t-

d an

d re

seat

pre

ssur

es w

ithin

the

UL

crite

ria

193

Man

ufac

ture

r BS

ingl

e42

War

m, D

amp

MS

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

Cou

ld n

ot a

djus

t reg

ulat

or d

own

to 1

1" W

.C.

197

Man

ufac

ture

r AS

ingl

e18

War

m, D

ryM

SR

ural

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

ΔX

O-

ΔO

Max

Loc

k-up

= 2

0.0"

W.C

.; R

egul

ator

cha

ttere

d an

d le

aked

thro

ugh

the

PR

D

at 1

00 p

sig

& 8

0 cf

h th

en s

topp

ed; P

RD

max

sta

rt-to

-dis

char

ge =

39.

2" W

.C.

199

Man

ufac

ture

r ASi

ngle

15W

arm

, Dry

MS

Rur

alE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

ΔA

djus

ting

scre

w a

ll th

e w

ay d

own;

low

out

let p

ress

ures

; Inl

et th

read

s ru

sty

201

Man

ufac

ture

r ASi

ngle

40W

arm

, Dry

MS

Rur

alE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

XLe

ak th

roug

h re

gula

tor;

Max

Loc

k-up

= 1

9" W

.C.

203

Man

ufac

ture

r ASi

ngle

11*

War

m, D

ryM

SR

ural

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

Adj

ustin

g sc

rew

all

the

way

dow

n; lo

w o

utle

t pre

ssur

es

226

Man

ufac

ture

r AS

ingl

e11

Coo

l, D

rySD

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

O-

O-

OO

Max

Loc

k-up

= 1

8.2"

W.C

.; pr

essu

re re

lief s

cree

n m

issi

ng

231

Man

ufac

ture

r ASi

ngle

22C

ool,

Dry

SD

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

OO

OO

ΔO

Max

sta

rt-to

-dis

char

ge =

34.

33" W

.C.

238

Man

ufac

ture

r BSi

ngle

55C

ool,

Dry

SD

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

ΔX

Leak

thro

ugh

regu

lato

r; M

ax L

ock-

up =

34.

4" W

.C.

241

Man

ufac

ture

r BSi

ngle

?C

ool,

Dry

SD

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

ΔO

OO

OO

Rus

ty in

let f

ittin

g; g

aske

t bro

ken

arou

nd s

prin

g co

ver

292

Man

ufac

ture

r AS

ingl

e27

Coo

l, D

rySD

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

ΔO

OX

OP

ress

ure

relie

f scr

een

mis

sing

; slo

w lo

ck-u

p; M

ax s

tart-

to-d

isch

arge

= 3

3.9"

W

.C.;

Max

lock

-up

= 18

" W.C

.

313

Man

ufac

ture

r AS

ingl

e16

War

m, D

ryM

SR

ural

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

O-

--

XO

Max

sta

rt-to

-dis

char

ge =

43"

W.C

.; M

ax lo

ck-u

p =

23.3

" W.C

.

353

Man

ufac

ture

r AS

ingl

e15

War

m, D

amp

MS

Rur

alE

nd o

f man

ufac

ture

r's re

com

men

ded

serv

ice

life

OX

Reg

ulat

or c

hatte

rs; l

eaks

thro

ugh

PR

D a

t 30

cfh

358

Man

ufac

ture

r BS

ingl

e28

War

m, D

ryC

Aru

ral

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

XR

egul

ator

cha

tters

; lea

ks th

roug

h P

RD

at 3

0 cf

h

360

Man

ufac

ture

r BS

ingl

e50

War

m, D

ryC

Aru

ral

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

XR

egul

ator

cha

tters

; lea

ks th

roug

h P

RD

at 3

0 cf

h

362

Man

ufac

ture

r BS

ingl

e13

War

m, D

ryC

Aru

ral

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OR

egul

ator

out

let p

ress

ure

will

not

hol

d st

eady

374

Man

ufac

ture

r BS

ingl

e29

Coo

l, D

rySD

rura

lTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

Δ-

--

OO

Slo

w lo

ck-u

p; M

ax L

ock-

up =

30.

3" W

.C.

383

Man

ufac

ture

r BS

ingl

e43

Coo

l, D

rySD

rura

lO

O-

--

ΔO

Max

Loc

k-up

= 3

5.7"

W.C

.; M

ax s

tart-

to-d

isch

arge

= 3

6" W

.C.

397

Man

ufac

ture

r AS

ingl

e23

War

m, D

ryAZ

rura

lC

hang

ed fr

om s

ingl

e to

dua

l reg

ulat

or u

seO

ΔR

egul

ator

will

not

lock

-up;

max

pre

ssur

e be

fore

test

sto

pped

= 1

9.7"

W.C

.

400

Man

ufac

ture

r AS

ingl

e16

War

m, D

rySC

rura

lO

ΔX

Reg

ulat

or le

aked

thro

ugh

PR

D a

t 30

cfh

407

Man

ufac

ture

r AS

ingl

e12

War

m, D

rySC

urba

nTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

O-

OO

XO

Max

Loc

k-up

= 1

3.8"

W.C

.; M

ax s

tart-

to-d

isch

arge

= 3

3.3"

W.C

.

O Δ X O Δ X O + - X O Δ X * **Th

e ty

pe o

f reg

ulat

or m

arke

d is

inco

nsis

tent

with

the

reas

on fo

r rem

oval

Can

not s

et in

itial

pre

ssur

e du

ring

regu

lato

r adj

ustm

ent;

pres

sure

fluc

tuat

es a

nd/o

r nev

er re

ache

s se

tpoi

nt

Reg

ulat

or d

id n

ot m

eet U

L 14

4 pr

essu

re re

lief s

tart-

to d

isch

arge

and

/or r

esea

ting

crite

ria fo

r a n

ew re

gula

tor i

n 1

out o

f 3 tr

ials

(usu

ally

occ

urre

d on

the

first

tria

l)

Reg

ulat

or d

id n

ot m

eet U

L 14

4 pr

essu

re re

lief s

tart-

to d

isch

arge

and

/or r

esea

ting

crite

ria fo

r a n

ew re

gula

tor i

n 2

or 3

tria

ls o

ut o

f 3.

Rea

son

for r

egul

ator

rem

oval

mar

ked

is in

cons

iste

nt w

ith th

e m

anuf

actu

rer's

dat

e st

amp

Pre

ssur

e re

lief d

evic

e di

d no

t ven

t

Reg

ulat

or m

issi

ng e

ssen

tial c

ompo

nent

s (b

onne

t cap

; out

er s

crew

s, e

tc.)

Reg

ulat

or s

how

s si

gns

of c

orro

sion

, wea

r, et

c. b

ut s

till t

este

d

GEN

ERA

L

LOC

K-U

PR

egul

ator

mee

ts lo

ck-u

p cr

iteria

for a

new

regu

lato

r as

spec

ified

in U

L 14

4

Reg

ulat

or d

id n

ot m

eet U

L 14

4 lo

ck-u

p cr

iteria

for a

new

regu

lato

r in

1 ou

t of 3

tria

ls b

ut lo

cked

-up

low

er th

an th

e pr

essu

re re

lief s

tart-

to-d

isch

arge

(UL

144

< Lo

ck-u

p <

PRD

std

)

Reg

ulat

or d

id n

ot m

eet U

L 14

4 lo

ck-u

p cr

iteria

for a

new

regu

lato

r in

3 ou

t of 3

tria

ls b

ut lo

cked

-up

low

er th

an th

e pr

essu

re re

lief s

tart-

to-d

isch

arge

(UL

144

< Lo

ck-u

p <

PRD

std

)

Reg

ulat

or le

aked

thro

ugh

PR

D d

urin

g lo

ck-u

p te

stin

g (P

RD

std

< L

ock-

up)

Reg

ulat

or d

id n

ot m

eet U

L 14

4 lo

ck-u

p cr

iteria

for a

new

regu

lato

r in

2 ou

t of 3

tria

ls b

ut lo

cked

-up

low

er th

an th

e pr

essu

re re

lief s

tart-

to-d

isch

arge

(UL

144

< Lo

ck-u

p <

PRD

std

)

Reg

ulat

or in

goo

d co

nditi

on; n

o vi

sibl

e si

gn o

f a p

robl

em

Test

s no

t con

duct

ed

KEY

EXTE

RN

AL IN

SPEC

TIO

N

PRES

SUR

E R

ELIE

FR

egul

ator

mee

ts p

ress

ure

relie

f sta

rt-to

-dis

char

ge a

nd re

seat

ing

crite

ria fo

r a n

ew re

gula

tor a

s sp

ecifi

ed in

UL

144

Reg

ulat

or le

aked

thro

ugh

PR

D d

urin

g ad

just

men

t

INTE

RN

AL

ADJU

STM

ENT

Reg

ulat

or in

goo

d co

nditi

on; n

o vi

sibl

e si

gn o

f a p

robl

em

Reg

ulat

or s

how

s si

gns

of c

orro

sion

, wea

r, st

iff/fr

ozen

spr

ings

, slo

w to

reac

h se

tpoi

nt, e

tc. b

ut s

till t

este

d

SIN

GLE

STA

GE

REG

ULA

TOR

S

REA

SON

FO

R F

AILU

RE

INSP

ECTI

ON

SR

EGU

LATO

R IN

FOR

MAT

ION

PRES

SUR

E R

ELIE

FLO

CK

-UP

Tab

le 5

. Ove

rvie

w o

f int

egra

l tw

o-st

age

regu

lato

r pe

rfor

man

ce.

Tab

le 6

. Ove

rvie

w o

f sin

gle-

stag

e re

gula

tor

perf

orm

ance

.

Reg

ulat

or ID

Reg

ulat

or

Man

ufac

ture

r:R

egul

ator

Ty

peR

egul

ator

A

ge (y

ears

)C

limat

eR

egul

ator

Lo

catio

n St

ate

Serv

ice

Are

aR

easo

n fo

r Reg

ulat

or R

emov

alEx

tern

al

Visu

al

Insp

ectio

n

Inte

rnal

In

spec

tion

and

Adj

ustm

ent

Mod

erat

e In

let

Pres

sure

Low

Inle

t Pr

essu

reH

igh

Inle

t Pr

essu

re

Star

t-to-

Dis

char

ge

Pres

sure

Res

eatin

g Pr

essu

re

13M

anuf

actu

rer A

Inte

gral

2-

stag

e13

War

m, D

amp

ALR

ural

Faul

ty re

gula

tor

-O

-O

OSl

ow lo

ck-u

p; M

ax L

ock-

up =

21.

9" W

.C.

18M

anuf

actu

rer B

Inte

gral

2-

stag

e7

Coo

l, D

amp

WA

Urb

anTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

ΔX

Leak

thro

ugh

PRD

at 1

00 p

sig

inle

t pre

ssur

e an

d hi

gh fl

ow ra

te (8

0 cf

h)

54M

anuf

actu

rer A

Twin

sta

ge7

War

m, D

ryK

SR

ural

Faul

ty re

gula

tor

-O

XLe

ak th

roug

h re

gula

tor;

Max

Loc

k-up

= 1

7" W

.C.;

PRD

did

not

ven

t

83M

anuf

actu

rer B

Inte

gral

2-

Sta g

e9

Coo

l, D

ryS

DR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OO

OO

OO

O10

6M

anuf

actu

rer B

Inte

gral

2-

Sta g

e11

Coo

l, D

amp

AK

Rur

alFa

ulty

regu

lato

rO

OO

OO

XO

Max

sta

rt-to

-dis

char

ge p

ress

ure

= 33

.7" W

.C.

107

Man

ufac

ture

r BIn

tegr

al 2

-St

age

13C

ool,

Dam

pA

KR

ural

Faul

ty re

gula

tor

XLe

ak th

roug

h re

gula

tor a

t 100

psi

g in

let p

ress

ure

and

0 cf

h (lo

ck-u

p); M

ax

Lock

-up

= 30

.9" W

.C.

108

Man

ufac

ture

r BIn

tegr

al 2

-St

age

11C

ool,

Dam

pA

KR

ural

Oth

er: u

pgra

deO

Δ-

--

OO

Slow

lock

-up;

Max

Loc

k-up

= 1

5.4"

W.C

.

116

Man

ufac

ture

r BIn

tegr

al 2

-St

age

10C

ool,

Dam

pW

ASu

burb

anO

ther

OX

Leak

s th

roug

h PR

D a

t 30

cfh

and

100

psig

inle

t pre

ssur

e

329

Man

ufac

ture

r AIn

tegr

al 2

-St

age

7C

ool,

Dry

SD

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nD

ID N

OT

TES

T - A

djus

ting

sprin

g fro

zen

in p

lace

330

Man

ufac

ture

r ATw

in S

tage

5C

ool,

Dry

SD

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

O-

OO

OO

Max

Loc

k-up

= 1

3.3"

W.C

.

339

Man

ufac

ture

r BTw

in S

tage

5C

ool,

Dam

pW

ASu

burb

anTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

OO

OO

OO

Inle

t and

out

let f

ittin

gs ru

sty

and

diffi

cult

to re

mov

e

340

Man

ufac

ture

r BTw

in S

tage

10C

ool,

Dam

pW

ASu

burb

anTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

ΔO

XLe

aks

thro

ugh

regu

lato

r whe

n ad

just

ing

from

80

cfh

to 3

0 cf

h at

100

psi

g an

d 25

psi

g in

let p

ress

ures

342

Man

ufac

ture

r BTw

in S

tage

4C

ool,

Dam

pW

Asu

burb

anta

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

OO

OO

OO

347

Man

ufac

ture

r BIn

tegr

al 2

-St

age

13C

ool,

Dam

pA

KR

ural

Faul

ty re

gula

tor

OO

OO

XSt

arte

d to

leak

thro

ugh

the

pres

sure

relie

f at 2

50 p

sig

inle

t pre

ssur

e

348

Man

ufac

ture

r BIn

tegr

al 2

-St

age

1C

ool,

Dam

pA

KR

ural

Oth

erO

OO

OO

ΔO

Max

sta

rt-to

-dis

char

ge =

34.

4" W

.C.

354

Man

ufac

ture

r BIn

tegr

al 2

-St

age

5W

arm

, Dry

CA

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

OO

OO

OO

475

Man

ufac

ture

r BC

ombo

11W

arm

, Dry

NJ

Subu

rban

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OX

Reg

ulat

or le

aks

thro

ugh

PR

D a

t 30

cfh

and

100

psig

inle

t

476

Man

ufac

ture

r BC

ombo

13W

arm

, Dry

NJ

Urb

anEn

d of

man

ufac

ture

r's re

com

men

ded

serv

ice

life

OO

OO

XLe

aks

thro

ugh

PRD

at 0

.5 c

fh a

nd 2

50 p

sig

inle

t

477

Man

ufac

ture

r BC

ombo

9W

arm

, Dry

NJ

Subu

rban

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OO

OO

OO

ΔP

RD

rese

atin

g pr

essu

re =

18.

2" W

.C.

490

Man

ufac

ture

r BIn

tegr

al 2

-S

tage

**6

War

m, D

amp

FLSu

burb

anC

hang

ed fr

om s

ingl

e to

dua

l reg

ulat

or s

yste

mO

XR

egul

ator

cha

tters

; lea

ks th

roug

h P

RD

at 3

0 cf

h an

d 10

0 ps

ig in

let

637

Man

ufac

ture

r BC

ombo

28W

arm

, Dry

NJ

Rur

alFa

ulty

regu

lato

r: le

aks

OO

OO

OX

OM

ax s

tart-

to-d

isch

arge

pre

ssur

e =

36.7

" W.C

.

O Δ X O Δ X O + - X O Δ X * **Th

e ty

pe o

f reg

ulat

or m

arke

d is

inco

nsis

tent

with

the

reas

on fo

r rem

oval

Can

not s

et in

itial

pre

ssur

e du

ring

regu

lato

r adj

ustm

ent;

pres

sure

fluc

tuat

es a

nd/o

r nev

er re

ache

s se

tpoi

nt

Reg

ulat

or d

id n

ot m

eet U

L 14

4 pr

essu

re re

lief s

tart-

to d

isch

arge

and

/or r

esea

ting

crite

ria fo

r a n

ew re

gula

tor i

n 1

out o

f 3 tr

ials

(usu

ally

occ

urre

d on

the

first

tria

l)

Reg

ulat

or d

id n

ot m

eet U

L 14

4 pr

essu

re re

lief s

tart-

to d

isch

arge

and

/or r

esea

ting

crite

ria fo

r a n

ew re

gula

tor i

n 2

or 3

tria

ls o

ut o

f 3.

Rea

son

for r

egul

ator

rem

oval

mar

ked

is in

cons

iste

nt w

ith th

e m

anuf

actu

rer's

dat

e st

amp

Pres

sure

relie

f dev

ice

did

not v

ent

Reg

ulat

or m

issi

ng e

ssen

tial c

ompo

nent

s (b

onne

t cap

; out

er s

crew

s, e

tc.)

Reg

ulat

or s

how

s si

gns

of c

orro

sion

, wea

r, et

c. b

ut s

till t

este

d

GEN

ERAL

LOC

K-U

PR

egul

ator

mee

ts lo

ck-u

p cr

iteria

for a

new

regu

lato

r as

spec

ified

in U

L 14

4

Reg

ulat

or d

id n

ot m

eet U

L 14

4 lo

ck-u

p cr

iteria

for a

new

regu

lato

r in

1 ou

t of 3

tria

ls b

ut lo

cked

-up

low

er th

an th

e pr

essu

re re

lief s

tart-

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Performance, Durability, and Service Life of 42 September 2006 Low Pressure Propane Vapor Regulators Battelle

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Performance, Durability, and Service Life of 43 September 2006 Low Pressure Propane Vapor Regulators Battelle

5.3.1 Summary of Lock-up Test Results

Regulator lock-up was measured at three different inlet pressures and recorded in three successive trials for each inlet pressure. For first-stage, integral two-stage, and single-stage regulators lock-up was measured at 100 psig, 25 psig, and 250 psig inlet pressures while lock-up for second-stage regulators was recorded at 10 psig, 5 psig, and 15 psig inlet pressures. Figures 22 through 39 compare the outlet pressure at lock-up to the test criteria and age for the regulators tested in this program. First-Stage Regulators Figures 22 through 30 compare the lock-up pressures to the test criteria and age for the first-stage regulators tested in this program (includes 10 psi, 5 psi, and 15 psi set regulators). Discussion of the first-stage regulator results is primarily focused on the 10 psi regulators as these regulators comprised the majority of the first-stage regulator samples collected. Only two 5-psi regulators and twenty-one 15 psi regulators were received for testing. The results for these regulators are shown in Figures 25 through 30. A general overview of first-stage regulator performance is provided in Table 3 of the previous section.

The results show that the lock-up test performance of first-stage regulators remains fairly consistent between regulators regardless of age and for the most part remains within the UL 144 criteria for new regulators. Only three of the regulators exceeded the UL 144 test criteria for new regulators at 100 psig inlet pressure and ranged in age from 14 to 41 years. These same regulators that did not meet the UL 144 criteria for new regulators were from three different environmental conditions and two different manufacturers. Based on these charts, there does not appear to be a significant correlation between regulator performance and age, environment, or manufacturer for first-stage regulators. One regulator supplied by the marketers was listed as a faulty regulator. Details for the regulators that did not meet the UL 144 criteria for new regulators are provided in Table 7. It should be noted that Figures 22 through 30 do not show regulators that failed to perform during adjustment. These regulators are discussed further in Section 5.3.5.

Page 62: Performance, Durability, and Service Life of Low Pressure ... · Performance, Durability, and Service Life of vii September 2006 Low Pressure Propane Vapor Regulators Battelle Of

Performance, Durability, and Service Life of 44 September 2006 Low Pressure Propane Vapor Regulators Battelle

Table 7. First-stage regulators that did not meet the

UL 144 lock-up criteria for new regulators. Regulator

ID Manuf. Age Climate StateService Area Reason for Removal

Reason for Not Meeting UL Criteria

267 B 41 Cool, Dry

IA Rural End of manuf. recom. service life

Outlet pressure would not stabilize; high lock-up

275 A 47 Cool, Dry

IA Rural End of manuf. recom. service life

Leak through regulator; pressure continued to climb

474 B 16 Warm, Dry

NJ Suburban End of manuf. recom. service life

High lock-up

538 A 16 Warm, Dry

PA Suburban Tank and regulator removed from service

Leak through PRD at 25 psi inlet pressure

593 A 17 Cool, Damp

ME Rural Tank and regulator removed from service

Slow lock-up at 100 psi inlet pressure

614 A 22 Cool, Dry

IA Rural End of manuf. recom. service life

High lock-up

783 B 14 Warm, Damp

MS -- Faulty regulator Outlet pressure would not stabilize; high lock-up

0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 20 22 24 25 26 27 28 30 31 32 39 40 41 42 43 46 48 57

Age

Out

let P

ress

ure

at L

ock-

up (p

si)

Max Min Average

783

538

267

130% of the Outlet Set Pressure ### Regulator ID

Figure 22. Lock-up pressures and age for 10 psi first-stage regulators

at 100 psig inlet pressure.

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Performance, Durability, and Service Life of 45 September 2006 Low Pressure Propane Vapor Regulators Battelle

0.00

1.00

2.00

3.00

4.00

5.00

6.00

7.00

8.00

9.00

10.00

11.00

12.00

13.00

14.00

15.00

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 20 22 24 25 26 27 28 30 31 32 39 40 41 42 43 46 48 57

Age

Out

let P

ress

ure

at L

ock-

up (p

si)

Max Min Average

538593

130% of the Outlet Set Pressure ### Regulator ID

Figure 23. Lock-up pressures and age for 10 psi first-stage regulators at 25 psig inlet pressure.

0.00

1.00

2.00

3.00

4.00

5.00

6.00

7.00

8.00

9.00

10.00

11.00

12.00

13.00

14.00

15.00

16.00

17.00

18.00

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 20 22 24 25 26 27 28 30 31 32 39 40 41 42 43 46 48 57

Age

Out

let P

ress

ure

at L

ock-

up (p

si)

Max Min Average

150% of the Outlet Set Pressure ### Regulator ID

474

614

Figure 24. Lock-up pressures and age for 10 psi first-stage regulators

at 250 psig inlet pressure.

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Performance, Durability, and Service Life of 46 September 2006 Low Pressure Propane Vapor Regulators Battelle

2447

0.00

0.50

1.00

1.50

2.00

2.50

3.00

3.50

4.00

4.50

5.00

5.50

6.00

6.50

7.00

15 17

Age

Out

let P

ress

ure

at L

ock-

up (p

si)

Max Min Average

130% of the Outlet Set Pressure ### Regulator ID

Figure 25. Lock-up pressures and age for 5 psi first-stage regulators

at 100 psig inlet pressure.

2447

0.00

0.50

1.00

1.50

2.00

2.50

3.00

3.50

4.00

4.50

5.00

5.50

6.00

6.50

7.00

15 17

Age

Out

let P

ress

ure

at L

ock-

up (p

si)

Max Min Average

130% of the Outlet Set Pressure ### Regulator ID

Figure 26. Lock-up pressures and age for 5 psi first-stage regulators

at 25 psig inlet pressure.

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Performance, Durability, and Service Life of 47 September 2006 Low Pressure Propane Vapor Regulators Battelle

2447

0.00

0.50

1.00

1.50

2.00

2.50

3.00

3.50

4.00

4.50

5.00

5.50

6.00

6.50

7.00

7.50

8.00

15 17

Age

Out

let P

ress

ure

at L

ock-

up (p

si)

Max Min Average

150% of the Outlet Set Pressure ### Regulator ID

Figure 27. Lock-up pressures and age for 5 psi first-stage regulators

at 250 psig inlet pressure.

0.001.002.003.004.005.006.007.008.009.00

10.0011.0012.0013.0014.0015.0016.0017.0018.0019.0020.0021.0022.0023.0024.0025.0026.0027.00

9 10 15 16 17 18 20 24 27 32 33 41 42 43 45 47 49 50

Unkno

wn

Age

Out

let P

ress

ure

at L

ock-

up (p

si)

Max Min Average

130% of the Outlet Set Pressure ### Regulator ID

275

Figure 28. Lock-up pressures and age for 15 psi first-stage regulators

at 100 psig inlet pressure.

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Performance, Durability, and Service Life of 48 September 2006 Low Pressure Propane Vapor Regulators Battelle

0.00

1.00

2.00

3.00

4.00

5.00

6.00

7.00

8.00

9.00

10.00

11.00

12.00

13.00

14.00

15.00

16.00

17.00

18.00

19.00

20.00

9 10 15 16 17 18 20 24 27 32 33 41 42 43 45 47 49 50

Unkno

wn

Age

Out

let P

ress

ure

at L

ock-

up (p

si)

Max Min Average

130% of the Outlet Set Pressure ### Regulator ID

Figure 29. Lock-up pressures and age for 15 psi first-stage regulators

at 25 psig inlet pressure.

0.001.002.003.004.005.006.007.008.009.00

10.0011.0012.0013.0014.0015.0016.0017.0018.0019.0020.0021.0022.0023.00

9 10 15 16 17 18 20 24 27 32 33 41 42 43 45 47 49 50

Unkno

wn

Age

Out

let P

ress

ure

at L

ock-

up (p

si)

Max Min Average

150% of the Outlet Set Pressure ### Regulator ID

Figure 30. Lock-up pressures and age for 15 psi first-stage regulators

at 250 psig inlet pressure.

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Performance, Durability, and Service Life of 49 September 2006 Low Pressure Propane Vapor Regulators Battelle

Second-Stage Regulators A general overview of all second-stage regulators tested in this program was provided in Table 4. Figures 31 through 33 compare the lock-up pressures to the test criteria and age for the second-stage regulators tested in this program. Note that regulators that failed to perform during adjustment are not included in these figures, but are addressed in Section 5.3.5.

The performance of second-stage regulators was more scattered than for the first-stage regulators, with the number of regulators not meeting the test criteria showing an increase past 35 years of age. Ten second-stage regulators did not meet the UL 144 lock-up criteria for new regulators, tending to increase significantly past 35 years of age. Six regulators that did not meet the UL 144 criteria were from a cool, dry environment; however, this may be because a larger sample size from this environment was received for testing. Additionally, six of the regulators with lock-up that did not meet the UL 144 criteria were from Manufacturer B. Details for the regulators that did not meet the UL 144 criteria for new regulators are provided in Table 8.

Table 8. Second-stage regulators that did not meet the UL 144 lock-up criteria for new regulators.

Regulator

ID Manuf. Age Climate StateService Area Reason for Removal

Reason for Not Meeting UL Criteria

42 B 16 Warm, Dry

IL Suburban End of manuf. recom. service life

High lock-up pressure

47 A -- Cool, Dry

SD Rural High lock-up pressure; regulator chatters

68 B 13 Cool, Damp

OH Suburban Tank and regulator removed from service

High lock-up pressure; high PRD start-to-discharge

pressure 90 B 46 Cool,

Dry SD Rural Tank and regulator

removed from service High lock-up pressure;

pressure would not stabilize 100 D 44 Cool,

Dry PA Suburban Service work at customer

location and found old regulator

Very rusty; high lock-up pressure

228 B 47 Cool, Dry

SD Rural Tank and regulator removed from service

High lock-up pressure; high PRD start-to-discharge

pressure 256 B 40 Cool,

Dry IA Rural End of manuf. recom.

service life Dirty inside regulator; High

lock-up pressure; Leak through regulator

257 B 36 Cool, Dry

IA Rural End of manuf. recom. service life

High lock-up pressure

345 A 4 Warm, Dry

KY Rural Other High lock-up pressure; high PRD start-to-discharge

pressure 534 A 25 Cool,

Damp PA Suburban End of manuf. recom.

service life High lock-up pressure

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Performance, Durability, and Service Life of 50 September 2006 Low Pressure Propane Vapor Regulators Battelle

0.00

1.00

2.00

3.00

4.00

5.00

6.00

7.00

8.00

9.00

10.00

11.00

12.00

13.00

14.00

15.00

16.00

17.00

18.00

19.00

20.00

21.00

22.00

1 2 3 4 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 25 26 27 28 30 31 32 33 34 35 36 37 38 39 40 41 42 44 47 48 U

Age

Out

let P

ress

ure

at L

ock-

up (i

nche

s W

.C.)

Max Min Average

345 68

42

257 256

100

90

22847

120% of the Outlet Set Pressure ### Regulator ID

Figure 31. Lock-up pressures and age for second-stage regulators

at 10 psig inlet pressure.

0.00

1.00

2.00

3.00

4.00

5.00

6.00

7.00

8.00

9.00

10.00

11.00

12.00

13.00

14.00

15.00

16.00

17.00

18.00

19.00

20.00

21.00

22.00

1 2 3 4 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 25 26 27 28 30 31 32 33 34 35 36 37 38 39 40 41 42 44 47 48 U

Age

Out

let P

ress

ure

at L

ock-

up (i

nche

s W

.C.)

Max Min Average

345

42

534

25790

22847

120% of the Outlet Set Pressure ### Regulator ID

Figure 32. Lock-up pressures and age for second-stage regulators

at 5 psig inlet pressure.

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Performance, Durability, and Service Life of 51 September 2006 Low Pressure Propane Vapor Regulators Battelle

0.00

1.00

2.00

3.00

4.00

5.00

6.00

7.00

8.00

9.00

10.00

11.00

12.00

13.00

14.00

15.00

16.00

17.00

18.00

19.00

20.00

21.00

22.00

1 2 3 4 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 25 26 27 28 30 31 32 33 34 35 36 37 38 39 40 41 42 44 47 48 U

Age

Out

let P

ress

ure

at L

ock-

up (i

nche

s W

.C.)

Max Min Average

42

25790

160% of the Outlet Set Pressure ### Regulator ID

Figure 33. Lock-up pressures and age for second-stage regulators

at 15 psig inlet pressure. Integral Two-Stage Regulators Figures 34 through 36 compare the lock-up pressures to the test criteria and age for the integral two-stage regulators tested in this program. The performance of the integral two-stage regulators from the small sample size received for this program was marginal. Of the 17 two-stage regulators to undergo lock-up testing five regulators during the 100 psig inlet pressure test did not meet the UL 144 criteria for new regulators. The percentage of two-stage regulators not meeting the UL 144 criteria for lock-up is significantly higher than that for both first- and second-stage regulators. Three of the five regulators that did not meet the lock-up test criteria were listed as faulty regulators by the marketer. There does not appear to be a trend in environmental location or manufacturers for the two-stage regulators that did not meet the test criteria. Details for the regulators that did not meet the test criteria are provided in Table 9. It should be noted that Figures 34 through 36 do not show regulators that failed to perform during adjustment. These regulators are discussed further in Section 5.3.5. A general overview of integral two-stage regulator performance is provided in Table 5.

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Performance, Durability, and Service Life of 52 September 2006 Low Pressure Propane Vapor Regulators Battelle

Table 9. Integral two-stage regulators that did not meet the

UL 144 lock-up criteria for new regulators. Regulator

ID Manuf. Age Climate StateService Area Reason for Removal

Reason for Not Meeting UL Criteria

13 A 13 Warm, Damp

AL Rural Faulty regulator High lock-up pressure

54 A 7 Warm, Dry

KS Rural Faulty regulator High lock-up pressure; PRD did not relieve

107 B 13 Cool, Damp

AK Rural Faulty regulator Leak through regulator

108 B 11 Cool, Damp

AK Rural Other: upgrade High lock-up pressure

330 A 5 Cool, Dry

SD Rural Tank and regulator removed from

service

High lock-up pressure

0.001.002.003.004.005.006.007.008.009.00

10.0011.0012.0013.0014.0015.0016.0017.0018.0019.0020.0021.0022.0023.0024.0025.0026.0027.0028.0029.0030.0031.00

1 4 5 6 7 9 10 11 13 28

Age

Out

let P

ress

ure

at L

ock-

up (i

nche

s W

.C.)

Max Min Average

54108

107

120% of the Outlet Set Pressure ### Regulator ID

330

13

Figure 36. Lock-up pressures and age for integral two-stage regulators

at 100 psig inlet pressure.

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Performance, Durability, and Service Life of 53 September 2006 Low Pressure Propane Vapor Regulators Battelle

0.00

1.00

2.00

3.00

4.00

5.00

6.00

7.00

8.00

9.00

10.00

11.00

12.00

13.00

14.00

15.00

16.00

17.00

1 4 5 6 7 9 10 11 13 28

Age

Out

let P

ress

ure

at L

ock-

up (i

nche

s W

.C.)

Max Min Average

54

108

120% of the Outlet Set Pressure ### Regulator ID

Figure 35. Lock-up pressures and age for integral two-stage regulators

at 25 psig inlet pressure.

0.00

1.00

2.00

3.00

4.00

5.00

6.00

7.00

8.00

9.00

10.00

11.00

12.00

13.00

14.00

15.00

16.00

17.00

18.00

19.00

20.00

21.00

22.00

1 4 5 6 7 9 10 11 13 28

Age

Out

let P

ress

ure

at L

ock-

up (i

nche

s W

.C.)

Max Min Average

160% of the Outlet Set Pressure ### Regulator ID

13

Figure 36. Lock-up pressures and age for integral two-stage regulators

at 250 psig inlet pressure.

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Performance, Durability, and Service Life of 54 September 2006 Low Pressure Propane Vapor Regulators Battelle

Single-Stage Regulators Figures 37 through 39 compare the lock-up pressures to the test criteria and age for the single-stage regulators tested in this program. The performance of single-stage regulators during the lock-up testing was poor. Of the 23 single-stage regulators to undergo lock-up testing 17 regulators during the 100 psig inlet pressure test did not meet the UL 144 criteria for new regulators. The percentage of single-stage regulators that did not meet the test criteria far exceeded the lock-up tests for the other regulator types. There appears to be a trend in the deterioration of regulator performance as related to age; although single-stage regulators of all ages did not perform well. There does not appear to be a significant trend in regulator performance as related to environmental location or manufacturer for single-stage regulators. More regulators from Manufacturer A did not meet the test criteria; however a larger sample of regulators from this manufacturer were tested. Details for the single-stage regulators that did not meet the test criteria are provided in Table 10.

Initially, regulators for testing were selected from all types (first-stage, second-stage, single-stage, and integral two-stage) that were provided for this study. However, after approximately 30 single-stage regulators were tested, it was decided to remove these from the sample pool. Although single-stage regulators are still in service, they are no longer permitted for new installations per the 1995 Edition of NFPA 58. For this reason, it was decided to focus on test samples consisting only of first-stage, second-stage, or integral two-stage regulators. It is likely we would have received more single-stage regulators had we not focused on collection of regulators designed for two-stage systems. It should be noted that Figures 37 through 39 do not show regulators that failed to perform during adjustment. These regulators are discussed further in Section 5.3.3. A general overview of single-stage regulator performance is provided in Table 6.

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Performance, Durability, and Service Life of 55 September 2006 Low Pressure Propane Vapor Regulators Battelle

Table 10. Single-stage regulators that did not meet the UL 144 lock-up criteria for new regulators.

Regulator

ID Manuf. Age Climate StateService Area Reason for Removal

Reason for Not Meeting UL Criteria

85 A 20 Cool, Dry

SD Rural Tank and regulator removed from service

High lock-up pressure; leak through PRD at high

flowrates 92 A 16 Cool,

Dry SD Rural Tank and regulator

removed from service High lock-up pressure

97 A 11 Cool, Dry

SD Rural High lock-up pressure

98 A 18 Cool, Dry

SD Rural Tank and regulator removed from service

Missing bonnet cap; high lock-up pressure

150 A 13 Warm, Dry

MS Rural Changed from single to dual regulator

system

High lock-up pressure

182 B 19 Warm, Damp

MS Rural Tank and regulator removed from service

Very rusty; high lock-up pressure

188 A 54 Warm, Damp

MS Rural Tank and regulator removed from service

Missing bonnet cap; high lock-up pressure

197 A 18 Warm, Dry

MS Rural End of manuf. recom. service life

High lock-up pressure; leaked through PRD

201 A 40 Warm, Dry

MS Rural End of manuf. recom. service life

Leak through regulator

226 A 11 Cool, Dry

SD Rural Tank and regulator removed from service

High lock-up pressure; missing vent screen

238 B 55 Cool, Dry

SD Rural Tank and regulator removed from service

Leak through regulator

313 A 16 Warm, Dry

MS Rural End of manuf. recom. service life

High lock-up pressure; high PRD start-to-discharge

pressure 374 B 29 Cool,

Dry SD Rural Tank and regulator

removed from service High lock-up pressure

383 B 43 Cool, Dry

SD Rural High lock-up pressure; high PRD start-to-discharge

pressure 397 A 23 Warm,

Dry AZ Rural Changed from single

to dual regulator system

Outlet pressure would not stabilize

400 A 16 Warm, Dry

SC Rural Leak through PRD

407 A 12 Warm, Dry

SC Rural Tank and regulator removed from service

High lock-up pressure; high PRD start-to-discharge

pressure

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Performance, Durability, and Service Life of 56 September 2006 Low Pressure Propane Vapor Regulators Battelle

0.001.002.003.004.005.006.007.008.009.00

10.0011.0012.0013.0014.0015.0016.0017.0018.0019.0020.0021.0022.0023.0024.0025.0026.0027.0028.0029.0030.0031.0032.0033.0034.0035.00

11 12 13 14 15 16 17 18 19 20 21 22 23 24 27 28 29 37 40 42 43 46 49 50 53 54

Unkno

wn

Unkno

wn

Unkno

wn

Age

Out

let P

ress

ure

at L

ock-

up (i

nche

s W

.C.)

Max Min Average

226

97407

150

313

400

92

197

98

182

85

397

374

201

383

188

238

120% of the Outlet Set Pressure ### Regulator ID

Figure 37. Lock-up pressures and age for single-stage regulators at 100 psig inlet pressure.

0.001.002.003.004.005.006.007.008.009.00

10.0011.0012.0013.0014.0015.0016.0017.0018.0019.0020.0021.0022.0023.0024.0025.0026.0027.0028.0029.0030.0031.00

11 12 13 14 15 16 17 18 19 20 21 22 23 24 27 28 29 37 40 42 43 46 49 50 53 54

Unkno

wn

Unkno

wn

Unkno

wn

Age

Out

let P

ress

ure

at L

ock-

up (i

nche

s W

.C.)

Max Min Average

313197

182

374

383

188

120% of the Outlet Set Pressure ### Regulator ID

Figure 38. Lock-up pressures and age for single-stage regulators at 25 psig inlet pressure.

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Performance, Durability, and Service Life of 57 September 2006 Low Pressure Propane Vapor Regulators Battelle

0.001.002.003.004.005.006.007.008.009.00

10.0011.0012.0013.0014.0015.0016.0017.0018.0019.0020.0021.0022.0023.0024.0025.0026.0027.0028.0029.0030.0031.0032.0033.0034.0035.0036.00

11 12 13 14 15 16 17 18 19 20 21 22 23 24 27 28 29 37 40 42 43 46 49 50 53 54

Unkno

wn

Unkno

wn

Unkno

wn

Age

Out

let P

ress

ure

at L

ock-

up (i

nche

s W

.C.)

Max Min Average

226 97 150

313

197

182

85 292

374

383

188

160% of the Outlet Set Pressure ### Regulator ID

Figure 39. Lock-up pressures and age for single-stage regulators at 250 psig inlet pressure.

5.3.2 Summary of Pressure Relief Test Results

The pressure relief device start-to-discharge and reseat pressures of each regulator were measured and recorded in three successive trials for each test. In these tests, the start-to-discharge pressure was measured by slowly pressuring the regulator until the first indication of air escaping was observed using the flow meter. In many cases the relief device did not open fully until the pressure was increased further. Subsequently, the pressure in the regulator was reduced carefully until no air flow from the pressure relief device was observed. This was recorded as the reseat pressure. After the initial sequence, the start-to-discharge pressure and reseating pressure tests were repeated two more times. Figures 40 through 51 compare the start-to-discharge and reseat pressures to the test criteria and age for the regulators tested in this program. First-Stage Regulators Figures 40 through 45 compare the start-to-discharge and reseat pressures to the test criteria and age for the first-stage regulators tested in this program. The test results were fairly consistent with only five out of 50 first-stage regulators not meeting the pressure relief test criteria, all of which had start-to-discharge and/or reseating pressures that were too low. An additional 30 first-stage regulators did not have integral relief valves and therefore did not undergo these tests. All regulators that did not meet the PRD test criteria were from Manufacturer B. Four out of the five regulators were under 15 years of age, one of which was listed as a faulty regulator by the

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Performance, Durability, and Service Life of 58 September 2006 Low Pressure Propane Vapor Regulators Battelle

marketer. Additionally, these regulators were either from a cool, dry or warm, dry environment. This data does not reflect regulator pressure relief performance for regulators older than 25 years of age since many of these regulators were not equipped with integral relief devices. Details for the first-stage regulators that did not meet the PRD test criteria are provided in Table 11. It should be noted that Figures 40 through 45 do not show regulators that failed to perform during adjustment. These regulators are discussed further in Section 5.3.5. A general overview of first-stage regulator performance is provided in Table 3.

Table 11. First-stage regulators that did not meet the UL 144 PRD criteria for new regulators.

Regulator ID Manuf. Age Climate State

Service Area Reason for Removal

Reason for Not Meeting UL Criteria

24 7

B 8 Cool, Dry

SD Rural Tank and regulator removed from service

PRD reseating pressure too low

361 B 27 Warm, Dry

CA Urban Tank and regulator removed from service

PRD start-to-discharge and reseating pressures too low; dirty exterior;

clean interior; could not adjust

440 B 6 Warm, Dry

SC Rural Other PRD reseating pressure too low; no adjustment

617 B 10 Cool, Dry

IA Rural Faulty regulator: Leaked PRD start-to-discharge and reseating pressures

too low 656 B 4 Cool,

Dry NY Urban Other: Relocated tank;

changed regs. PRD start-to-discharge and reseating pressures

too low

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Performance, Durability, and Service Life of 59 September 2006 Low Pressure Propane Vapor Regulators Battelle

0.001.002.003.004.005.006.007.008.009.00

10.0011.0012.0013.0014.0015.0016.0017.0018.0019.0020.0021.0022.0023.0024.0025.0026.00

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 20 22 24 25 26 27 28 30 31 32 39 40 41 42 43 46 48 57

Age

Rel

ief S

tart

-to-D

isch

are

Pres

sure

(psi

)

Max Min Average

656

361

57

250% of the Outlet Set Pressure 140% of the Outlet Set Pressure ### Regulator ID

617

Figure 40. Start-to-discharge pressures and age for 10 psi first-stage regulators.

0.00

1.00

2.00

3.00

4.00

5.00

6.00

7.00

8.00

9.00

10.00

11.00

12.00

13.00

14.00

15.00

16.00

17.00

18.00

19.00

20.00

21.00

22.00

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 20 22 24 25 26 27 28 30 31 32 39 40 41 42 43 46 48 57

Age

Rel

ief R

esea

ting

Pres

sure

(psi

)

Max Min Average

656 361

57

440

247

140% of the Outlet Set Pressure ### Regulator ID

617

Figure 41. Reseat pressures and age for 10 psi first-stage regulators.

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Performance, Durability, and Service Life of 60 September 2006 Low Pressure Propane Vapor Regulators Battelle

2447

0.000.501.001.502.002.503.003.504.004.505.005.506.006.507.007.508.008.509.009.50

10.0010.5011.0011.5012.0012.5013.00

15 17

Age

Rel

ief S

tart

-to-D

isch

are

Pres

sure

(psi

)

Max Min Average

250% of the Outlet Set Pressure 140% of the Outlet Set Pressure ### Regulator ID

Figure 42. Start-to-discharge pressures and age for 5 psi first-stage regulators.

2447

0.00

0.50

1.00

1.50

2.00

2.50

3.00

3.50

4.00

4.50

5.00

5.50

6.00

6.50

7.00

7.50

8.00

8.50

9.00

15 17

Age

Rel

ief R

esea

ting

Pres

sure

(psi

)

Max Min Average

140% of the Outlet Set Pressure ### Regulator ID

Figure 43. Reseat pressures and age for 5 psi first-stage regulators.

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Performance, Durability, and Service Life of 61 September 2006 Low Pressure Propane Vapor Regulators Battelle

0.001.002.003.004.005.006.007.008.009.00

10.0011.0012.0013.0014.0015.0016.0017.0018.0019.0020.0021.0022.0023.0024.0025.0026.0027.0028.0029.0030.0031.0032.0033.0034.0035.0036.0037.0038.00

9 10 15 16 17 18 20 24 27 32 33 41 42 43 45 47 49 50

Unkno

wn

Age

Rel

ief S

tart

-to-D

isch

are

Pres

sure

(psi

)

Max Min Average

250% of the Outlet Set Pressure 140% of the Outlet Set Pressure ### Regulator ID

175

425

Figure 44. Start-to-discharge pressures and age for 15 psi first-stage regulators.

0.001.002.003.004.005.006.007.008.009.00

10.0011.0012.0013.0014.0015.0016.0017.0018.0019.0020.0021.0022.0023.0024.0025.0026.00

9 10 15 16 17 18 20 24 27 32 33 41 42 43 45 47 49 50

Unkno

wn

Age

Rel

ief R

esea

ting

Pres

sure

(psi

)

Max Min Average

140% of the Outlet Set Pressure ### Regulator ID

175

425

Figure 45. Reseat pressures and age for 15 psi first-stage regulators.

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Performance, Durability, and Service Life of 62 September 2006 Low Pressure Propane Vapor Regulators Battelle

Second-Stage Regulators Figures 46 through 47 compare the start-to-discharge and reseat pressures to the test criteria and age for the second-stage regulators tested in this program. The test results were widely scattered for reseating pressures regardless of regulator age. However, there does appear to be a slight age affect for the start-to-discharge pressures. More regulators older than 15 years tended to exceed the PRD test criteria than regulators less than 15 years in age. Of the 78 second-stage regulators that underwent the pressure relief tests 27 regulators did not meet the test criteria. Most of these regulators had start-to-discharge pressures that were too high ranging from 33.2 inches of water to 60.1 inches of water. One regulator still did not relieve after reaching 65 inches of water.

02468

10121416182022242628303234363840424446485052545658606264

1 2 3 4 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 25 26 27 28 30 31 32 33 34 35 36 37 38 39 40 41 42 44 47 48 U

Age

Rel

ief S

tart

-to-D

isch

are

Pres

sure

(inc

hes

W.C

.)

Max Min Average

300% of the Outlet Set Pressure 170% of the Outlet Set Pressure ### Regulator ID

345

445

68

30 221130

170

550

483 530691634

711

524

268

207

556

60

367

263 228

255

113502 469

Figure 46. Start-to-discharge pressures and age for second-stage regulators.

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Performance, Durability, and Service Life of 63 September 2006 Low Pressure Propane Vapor Regulators Battelle

0.00

2.00

4.00

6.00

8.00

10.00

12.00

14.00

16.00

18.00

20.00

22.00

24.00

26.00

28.00

30.00

32.00

34.00

36.00

1 2 3 4 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 25 26 27 28 30 31 32 33 34 35 36 37 38 39 40 41 42 44 47 48 U

Age

Rel

ief R

esea

ting

Pres

sure

(inc

hes

W.C

.)

Max Min Average

693

514

170% of the Outlet Set Pressure ### Regulator ID

Figure 47. Reseat pressures and age for second-stage regulators.

There does not appear to be a correlation between second-stage regulator relief performance and different environments and/or manufacturers. Details for the second-stage regulators that did not meet the PRD test criteria are provided in Table 12. It should be noted that Figures 46 through 47 do not show regulators that failed to perform during adjustment. These regulators are discussed further in Section 5.3.5. A general overview of second-stage regulator performance is provided in Table 4.

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Performance, Durability, and Service Life of 64 September 2006 Low Pressure Propane Vapor Regulators Battelle

Table 12. Second-stage regulators that did not meet the UL 144 PRD criteria for new regulators.

Reg. ID Manuf. Age Climate State

Service Area Reason for Removal Reason for Not Meeting UL Criteria

30 B 15 Cool, Dry IA Rural End of manuf. rec.om. service life PRD start-to-discharge pressure too high 60 A 37 Warm, Dry MS Rural Tank and regulator removed from

service PRD start-to-discharge pressure too high

68 B 13 Cool, Damp OH Suburban Tank and regulator removed from service

PRD start-to-discharge pressure too high

113 A 13 Cool, Dry NH Rural Other PRD start-to-discharge pressure too high for first trial 130 B 17 Warm,

Damp NC Suburban End of manuf. recom. service life PRD start-to-discharge pressure too high; fittings

rusty, difficult to remove 170 A 22 Warm, Dry KY Suburban End of manuf. recom. service life PRD start-to-discharge pressure too high; fittings

rusty, difficult to remove 207 A 34 Cool, Damp ME Rural Tank and regulator removed from

service PRD start-to-discharge pressure too high for first trial

221 A 15 Cool, Damp MI Rural End of manuf. recom. service life PRD start-to-discharge pressure too high; fittings rusty, difficult to remove

228 B 47 Cool, Dry SD Rural Tank and regulator removed from service

PRD start-to-discharge pressure too high for first trial; high lock-up pressure

255 B 32 Cool, Dry IA Rural End of manuf. recom. service life PRD start-to-discharge pressure too high 263 A 41 Cool, Dry IA Rural End of manuf. recom. service life PRD start-to-discharge pressure too high 268 A 32 Cool, Dry IA Rural End of manuf. recom. service life PRD start-to-discharge pressure too high; bolts in

regulator are rusty 345 A 4 Warm, Dry KY Rural Other PRD start-to-discharge pressure too high for first trial;

high lock-up 367 B 39 Warm,

Damp WA Urban Tank and regulator removed from

service PRD start-to-discharge pressure too high

445 B 6 Warm, Dry SC Rural Tank and regulator removed from service

PRD start-to-discharge pressure too high

469 A 41 Cool, Dry WI Urban End of manuf. recom. service life PRD start-to-discharge pressure too high for first trial 483 A 25 Cool, Damp IN Rural End of manuf. recom. service life PRD start-to-discharge pressure too high for first trial 502 B 20 Cool, Dry IA Rural End of manuf. recom. service life PRD start-to-discharge pressure too high 514 A 11 Warm,

Damp VA Rural Tank and regulator removed from

service PRD reseating pressure too low

524 B 31 Cool, Damp PA Suburban End of manuf. recom. service life PRD start-to-discharge pressure too high for first trial 530 B 25 Cool, Damp PA Suburban End of manuf. recom. service life PRD start-to-discharge pressure too high 550 B 22 Cool, Damp IN Rural End of manuf. recom. service life Very rusty; PRD start-to-discharge pressure too high 556 A 34 Cool, Damp IN Rural End of manuf. recom. service life PRD start-to-discharge pressure too high 634 A 25 Warm, Dry NJ Suburban End of manuf. recom. service life PRD start-to-discharge pressure too high for first trial 691 B 27 Cool, Dry SD Urban End of manuf. recom. service life PRD start-to-discharge pressure too high for first trial 693 B 8 Cool, Dry SD Rural Tank and regulator removed from

service PRD reseating pressure too low

711 A 27 Cool, Dry SD Rural End of manuf. recom. service life PRD did not relieve after reaching 65” W.C.

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Performance, Durability, and Service Life of 65 September 2006 Low Pressure Propane Vapor Regulators Battelle

Integral Two-Stage Regulators Figures 48 through 49 compare the start-to-discharge and reseat pressures to the test criteria and age for the integral two-stage regulators tested in this program. The test results were widely scattered regardless of regulator age. Of the 11 integral two-stage regulators that underwent the pressure relief tests four regulators did not meet the test criteria. Most of these regulators had start-to-discharge pressures that were too high ranging from 33.7 inches of water to 36.7 inches of water and ranged in age from 1 to 28 years. Additionally, two of the regulators that did not meet the test criteria were listed as “faulty regulators” by the marketer. All regulators that did not meet the pressure relief test criteria were from Manufacturer B and came from two specific locations. Such a small sample size makes it difficult to determine any trends between age, environmental conditions, and manufacturers and regulator performance. Details for the integral two-stage regulators that did not meet the PRD test criteria are provided in Table 13. It should be noted that Figures 48 through 49 do not show regulators that failed to perform during adjustment. These regulators are discussed further in Section 5.3.5. A general overview of integral two-stage regulator performance is provided in Table 5.

Table 13. Integral two-stage regulators that did not meet the UL 144 PRD criteria for new regulators.

Regulator

ID Manuf. Age Climate State Service Area Reason for Removal

Reason for Not Meeting UL Criteria

106 B 11 Cool, Damp

AK Rural Faulty Regulator PRD start-to-discharge pressure too high

348 B 1 Cool, Damp

AK Rural Other PRD start-to-discharge pressure too high

477 B 9 Warm, Dry

NJ Suburban Tank and regulator removed from service

PRD reseating pressure too low

637 B 28 Warm, Dry

NJ Rural Faulty Regulator: Leaks PRD start-to-discharge pressure too high

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Performance, Durability, and Service Life of 66 September 2006 Low Pressure Propane Vapor Regulators Battelle

0.00

2.00

4.00

6.00

8.00

10.00

12.00

14.00

16.00

18.00

20.00

22.00

24.00

26.00

28.00

30.00

32.00

34.00

36.00

1 4 5 6 7 9 10 11 13 28

Age

Rel

ief S

tart

-to-D

isch

are

Pres

sure

(inc

hes

W.C

.)

Max Min Average

348106

637

300% of the Outlet Set Pressure 170% of the Outlet Set Pressure ### Regulator ID

Figure 48. Start-to-discharge pressures and age for integral two-stage regulators.

0.00

2.00

4.00

6.00

8.00

10.00

12.00

14.00

16.00

18.00

20.00

22.00

24.00

26.00

28.00

30.00

32.00

34.00

1 4 5 6 7 9 10 11 13 28

Age

Rel

ief R

esea

ting

Pres

sure

(inc

hes

W.C

.)

Max Min Average

477

170% of the Outlet Set Pressure ### Regulator ID

Figure 49. Reseat pressures and age for integral two-stage regulators.

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Performance, Durability, and Service Life of 67 September 2006 Low Pressure Propane Vapor Regulators Battelle

Single-Stage Regulators Figures 50 through 51 compare the start-to-discharge and reseat pressures to the test criteria and age for the single-stage regulators tested in this program. The test results were widely scattered regardless of regulator age. Of the 17 single-stage regulators that underwent the pressure relief tests nearly half of the regulators (8) did not meet the test criteria. Most of these regulators had start-to-discharge pressures that were too high ranging from 33.5 inches of water to 43 inches of water and ranged in age from 12 to 43 years. Most regulators that did not meet the pressure relief test criteria were from Manufacturer A however more than two-thirds of the single-stage regulators received were from Manufacturer A. Most of the regulators that did not meet the test criteria were from a cool, dry or a warm, dry environment. Details for the single-stage regulators that did not meet the PRD test criteria are provided in Table 14. It should be noted that Figures 50 through 51 do not show regulators that failed to perform during adjustment. These regulators are discussed further in Section 5.3.5. A general overview of single-stage regulator performance is provided in Table 6.

Table 14. Single-stage regulators that did not meet the UL 144 PRD criteria for new regulators.

Regulator

ID Manuf. Age Climate State Service Area Reason for Removal

Reason for Not Meeting UL Criteria

67 A 27 Cool, Damp

OH Rural Tank and regulator removed from service

PRD start-to-discharge pressure too high

91 A 16 Cool, Dry SD Rural Tank and regulator removed from service

Stiff adjusting spring; PRD start-to-discharge

pressure too high 197 A 18 Warm,

Dry MS Rural End of manuf. recom.

service life High lock-up; Leak through PRD; PRD start-to-discharge pressure too high

231 A 22 Cool, Dry SD Rural Tank and regulator removed from service

PRD start-to-discharge pressure too high in

first trial 292 A 27 Cool, Dry SD Rural Tank and regulator

removed from service PRD start-to-discharge pressure too high; high

lock-up; PRD screen missing

313 A 16 Warm, Dry

MS Rural End of manuf. recom. service life

PRD start-to-discharge pressure too high; high

lock-up 383 B 43 Cool, Dry SD Rural PRD start-to-discharge

pressure too high in first trial; high lock-up

407 A 12 Warm, Dry

SC Urban Tank and regulator removed from service

PRD start-to-discharge pressure too high; high

lock-up

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Performance, Durability, and Service Life of 68 September 2006 Low Pressure Propane Vapor Regulators Battelle

0.002.004.006.008.00

10.0012.0014.0016.0018.0020.0022.0024.0026.0028.0030.0032.0034.0036.0038.0040.0042.0044.00

11 12 13 14 15 16 17 18 19 20 21 22 23 24 27 28 29 37 40 42 43 46 49 50 53 54

Unkno

wn

Unkno

wn

Unkno

wn

Age

Rel

ief S

tart

-to-D

isch

are

Pres

sure

(inc

hes

W.C

.)

Max Min Average

300% of the Outlet Set Pressure 170% of the Outlet Set Pressure ### Regulator ID

407

313

91

197

67292

383231

Figure 50. Start-to-discharge pressures and age for single-stage regulators.

0.00

2.00

4.00

6.00

8.00

10.00

12.00

14.00

16.00

18.00

20.00

22.00

24.00

26.00

28.00

30.00

32.00

34.00

11 12 13 14 15 16 17 18 19 20 21 22 23 24 27 28 29 37 40 42 43 46 49 50 53 54

Unkno

wn

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wn

Unkno

wn

Age

Rel

ief R

esea

ting

Pres

sure

(inc

hes

W.C

.)

Max Min Average

170% of the Outlet Set Pressure ### Regulator ID

Figure 51. Reseat pressures and age for single-stage regulators.

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Performance, Durability, and Service Life of 69 September 2006 Low Pressure Propane Vapor Regulators Battelle

5.3.3 Effects of Manufacturer on Regulator Performance

As previously mentioned, the numbers of regulators tested were fairly evenly distributed between two manufacturers, “A” and “B”, with over 125 of each manufacturer’s units tested. Figures 52 through 54 show the lockup pressures, relief start-to-discharge pressures, and relief reseat pressures for first-stage regulators, sorted by manufacturer. As the other previously discussed charts, the vertical axis is the parameter tested (lockup, etc.). The horizontal axis is an indication of the number of regulators tested. If there were significant differences between the manufacturers, there would be a noticeable variation of the vertical spread of the data points taken as a group (considering all regulators tested of one manufacturer). Another difference would be the variability of a particular regulator, displayed as vertically stacked points. On these charts, if one manufacturer’s units were more or less repeatable, it would be noticeable on these charts. These figures show neither of these variabilities, indicating that there is no significant difference in the data between the manufacturers. Similarly, Figures 55 through 56 show the lockup pressures, relief start-to-discharge pressure, and relief reseat pressure for second-stage regulators, sorted by brand, and Figures 58 through 60 show the lockup pressures, relief start-to-discharge pressure, and relief reseat pressure for single-stage regulators, sorted by brand. For these second-stage and single-stage regulators, there is also no significant difference in the data between the manufacturers.

0123456789

10111213141516

ManufacturerA

ManufacturerB

Manufacturer

Out

let P

ress

ure

at L

ock-

up (p

si)

Max Min Average

783

538

267

130% of the Outlet Set Pressure ### Regulator ID

Figure 52. Lock-up pressures and manufacturer for 10 psi first-stage regulators

at 100 psig inlet pressure.

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Performance, Durability, and Service Life of 70 September 2006 Low Pressure Propane Vapor Regulators Battelle

0123456789

1011121314151617181920212223242526

ManufacturerA

ManufacturerB

Manufacturer

Rel

ief S

tart

-to-D

isch

arge

Pre

ssur

e (p

si)

Max Min Average

656

361

250% of the Outlet Set Pressure 140% of the Outlet Set Pressure ### Regulator ID

617

Figure 53. Start-to-discharge pressures and manufacturer for 10 psi first-stage regulators.

0123456789

10111213141516171819202122

ManufacturerA

ManufacturerB

Manufacturer

Rel

ief R

esea

ting

Pres

sure

(psi

)

Max Min Average

656361

440247

140% of the Outlet Set Pressure ### Regulator ID

617

Figure 54. Reseat pressures and manufacturer for 10 psi first-stage regulators.

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Performance, Durability, and Service Life of 71 September 2006 Low Pressure Propane Vapor Regulators Battelle

0123456789

10111213141516171819202122

ManufacturerA

ManufacturerB

ManufactD

Manufacturer

Out

let P

ress

ure

at L

ock-

up (i

nche

s W

.C.)

Max Min Average

345 68

42

257256

100

90

22847

120% of the Outlet Set Pressure ### Regulator ID

Figure 55. Lock-up pressures and manufacturer for second-stage regulators

at 10 psig inlet pressure.

02468

10121416182022242628303234363840424446485052545658606264

ManufacturerA

ManufacturerB

ManufacturerD

Manufacturer

Rel

ief S

tart

-to-D

isch

arge

Pre

ssur

e (in

ches

W.C

.)

MaxMinAverage

300% of the Outlet Set Pressure 170% of the Outlet Set Pressure ### Regulator ID

Figure 56. Start-to-discharge pressures and manufacturer for second-stage regulators.

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Performance, Durability, and Service Life of 72 September 2006 Low Pressure Propane Vapor Regulators Battelle

02468

1012141618202224262830323436

ManufacturerA

ManufacturerB

ManufacturerD

Manufacturer

Rel

ief R

esea

ting

Pres

sure

(inc

hes

W.C

.)

MaxMinAverage693

514

170% of the Outlet Set Pressure ### Regulator ID

Figure 57. Reseat pressures and manufacturer for second-stage regulators.

02468

10121416182022242628303234

ManufacturerA

ManufacturerB

Manufacturer

Out

let P

ress

ure

at L

ock-

up (i

nche

s W

.C.)

Max Min Average

120% of the Outlet Set Pressure ### Regulator ID

Figure 58. Lock-up pressures and manufacturer for single-stage regulators

at 100 psig inlet pressure.

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Performance, Durability, and Service Life of 73 September 2006 Low Pressure Propane Vapor Regulators Battelle

02468

101214161820222426283032343638404244

ManufacturerA

ManufacturerB

Manufacturer

Rel

ief S

tart

-to-D

isch

arge

Pre

ssur

e (in

ches

W.C

.)

Max Min Average

300% of the Outlet Set Pressure 170% of the Outlet Set Pressure ### Regulator ID

407

313

91

197

67292

383231

Figure 59. Start-to-discharge pressures and manufacturer for single-stage regulators.

02468

10121416182022242628303234

ManufacturerA

ManufacturerB

Manufacturer

Rel

ief R

esea

ting

Pres

sure

(inc

hes

W.C

.)

Max Min Average

170% of the Outlet Set Pressure ### Regulator ID

Figure 60. Reseat pressures and age for single-stage regulators.

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Performance, Durability, and Service Life of 74 September 2006 Low Pressure Propane Vapor Regulators Battelle

Figure 61 shows a summary of the failed regulators. More regulators from Manufacturer A and B were tested than the other manufacturers as shown by Figure 11. Roughly 53 percent of the regulators tested were from Manufacturer A and approximately 47 percent were from Manufacturer B. Each of these showed similar range of results for lock-up, start-to-discharge, and reseat pressures. While the overall range was similar, more of the Manufacturer A regulators met the test criteria.

Figure 61. Regulator failures by regulator manufacturer.

5.3.4 Effects of Environment on Regulator Performance

The test data were replotted from the perspective of the four environmental regions, as shown in Figures 6 and 8:

- Warm; dry ( > 53°F; < 73% humidity), - Warm; damp ( > 53°F; > 73% humidity), - Cool; dry (< 53°F; < 73% humidity), and - Cool; damp (< 53°F; > 73% humidity).

The source environment comparison in Figures 62 through 70 shows fairly consistent behavior in pressure tests of lock-up, PRD start-to-discharge, and PRD reseat across each environment. Each environment shows similar scatter and range for these tests. Any of the apparent differences in scatter that the data might suggest are more likely to be the result of differences in the number of specimens from each environment. These plots do not suggest major differences in pressure test

43 out of 145

49 out of 129

0/20.0%

10.0%

20.0%

30.0%

40.0%

50.0%

60.0%

70.0%

80.0%

90.0%

100.0%

Manufacturer A Manufacturer B Other

% o

f Spe

cim

ens

% Failed in Group

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Performance, Durability, and Service Life of 75 September 2006 Low Pressure Propane Vapor Regulators Battelle

performance that are a result of source environment. However, Figure 71, which shows the number of failed regulators for the four environmental conditions, shows a higher percentage of failures from a warm, dry environment. With the number of samples being reasonably significant (much greater than ten units), the fact that nearly half of the warm, dry regulators failed to meet the test criteria is also significant. While internal and external corrosion may be considered a significant failure mechanism, perhaps the drying effects on elastomeric components such as seals and the diaphragm may be more significant.

0123456789

10111213141516

Cool,Damp

Cool,Dry

Warm,Damp

Warm,Dry

Environment

Out

let P

ress

ure

at L

ock-

up (p

si)

Max Min Average

783

538

267

130% of the Outlet Set Pressure ### Regulator ID

Figure 62. Lock-up pressures and environment for 10 psi first-stage regulators

at 100 psig inlet pressure.

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Performance, Durability, and Service Life of 76 September 2006 Low Pressure Propane Vapor Regulators Battelle

0123456789

1011121314151617181920212223242526

Cool,Damp

Cool,Dry

Warm,Damp

Warm,Dry

Environment

Rel

ief S

tart

-to-D

isch

arge

Pre

ssur

e (p

si)

Max Min Average

656

361

57

250% of the Outlet Set Pressure 140% of the Outlet Set Pressure ### Regulator ID

617

Figure 63. Start-to-discharge pressures and environment for 10 psi first-stage regulators.

0123456789

10111213141516171819202122

Cool,Damp

Cool,Dry

Warm,Damp

Warm,Dry

Environment

Rel

ief R

esea

ting

Pres

sure

(psi

)

Max Min Average

656 361

57

440247

140% of the Outlet Set Pressure ### Regulator ID

617

Figure 64. Reseat pressures and environment for 10 psi first-stage regulators.

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Performance, Durability, and Service Life of 77 September 2006 Low Pressure Propane Vapor Regulators Battelle

0123456789

10111213141516171819202122

Cool,Damp

Cool,Dry

Warm,Damp

Warm,Dry

Environment

Out

let P

ress

ure

at L

ock-

up (i

nche

s W

.C.)

Max Min Average

34568

42

257256

100

90

22847

120% of the Outlet Set Pressure ### Regulator ID

Figure 65. Lock-up pressures and environment for second-stage regulators

at 10 psig inlet pressure.

02468

10121416182022242628303234363840424446485052545658606264

Cool,Damp

Cool,Dry

Warm,Damp

Warm,Dry

Environment

Rel

ief S

tart

-to-D

isch

arge

Pre

ssur

e (in

ches

W.C

.)

Max Min Average

300% of the Outlet Set Pressure 170% of the Outlet Set Pressure ### Regulator ID

345

445

68

30221130

170550483 530 691 634

711

524

268

207

556

60

367

263228

255

113502469

Figure 66. Start-to-discharge pressures and environment for second-stage regulators.

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Performance, Durability, and Service Life of 78 September 2006 Low Pressure Propane Vapor Regulators Battelle

02468

1012141618202224262830323436

Cool,Damp

Cool,Dry

Warm,Damp

Warm,Dry

Environment

Rel

ief R

esea

ting

Pres

sure

(inc

hes

W.C

.)

Max Min Average

693

514

170% of the Outlet Set Pressure ### Regulator ID

Figure 67. Reseat pressures and environment for second-stage regulators.

02468

10121416182022242628303234

Cool,Damp

Cool,Dry

Warm,Damp

Warm,Dry

Environment

Out

let P

ress

ure

at L

ock-

up (i

nche

s W

.C.)

Max Average Series1 Series2

226

97407

150

313

400

92

197

98

182

85

397

374

201

383

188

238

120% of the Outlet Set Pressure ### Regulator ID

Figure 68. Lock-up pressures and environment for single-stage regulators

at 100 psig inlet pressure.

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Performance, Durability, and Service Life of 79 September 2006 Low Pressure Propane Vapor Regulators Battelle

02468

101214161820222426283032343638404244

Cool,Damp

Cool,Dry

Warm,Damp

Warm,Dry

Environment

Rel

ief S

tart

-to-D

isch

arge

Pre

ssur

e (in

ches

W.C

.)

Max Min Average

300% of the Outlet Set Pressure 170% of the Outlet Set Pressure ### Regulator ID

407

313

91

197

67292

383231

Figure 69. Start-to-discharge pressures and environment for single-stage regulators.

02468

10121416182022242628303234

Cool,Damp

Cool,Dry

Warm,Damp

Warm,Dry

Environment

Rel

ief R

esea

ting

Pres

sure

(inc

hes

W.C

.)

Max Min Average

170% of the Outlet Set Pressure ### Regulator ID

Figure 70. Reseat pressures and age for single-stage regulators.

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Performance, Durability, and Service Life of 80 September 2006 Low Pressure Propane Vapor Regulators Battelle

21 out of 6529 out of 10113 out of 47

29 out of 61

0.0%

10.0%

20.0%

30.0%

40.0%

50.0%

60.0%

70.0%

80.0%

90.0%

100.0%

Warm, Dry Warm, Damp Cool, Dry Cool, Damp

% o

f Spe

cim

ens

% Failed in Group

Figure 71. Regulator failures by regulator environment.

5.3.5 Causes of Regulator “Failures”

Identification of regulator failures was based on potential safety concerns related to system overpressurization and/or leaking gas. As such, the main causes of regulator failure identified in this test program include:

• Regulator chatters and leaks through the pressure relief device (PRD); • Leak in regulator body; • PRD start-to discharge and/or reseat pressure too low; • PRD start-to discharge pressure above the UL 144 specification; • Regulator discharge pressure will not stabilize; or • PRD did not relieve.

Additionally, a total of 5 regulators selected for testing were missing the bonnet cap. The bonnet cap protects the regulator from contaminants entering the regulator and damaging the diaphragm and/or creating corrosion problems. Since there was not a means to determine if problems associated with these regulators were due to the regulator itself or damage caused from the missing bonnet cap it was decided not to include test results for these regulators.

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Performance, Durability, and Service Life of 81 September 2006 Low Pressure Propane Vapor Regulators Battelle

Some regulators also exhibited lock-up pressures beyond the limits specified in UL 144 as shown in Section 5.3.1; however this result was not considered as a regulator failure. The belief is that even though the regulator is not functioning within the limits of a new regulator it may still be fit for service. Over time, the elastomer material in the seat disc is likely to permanently indent/deform from repeated opening and closing of the regulator. This permanent deformation of the seat disc may lead to a larger range in the regulator pressure performance curve but is not likely to lead to significant operational or safety issues. These regulators have been noted as such in the test results documentation. However, if the seat disc is permanently deformed to the point that it will not close, the regulator will exhibit very high lockup or may not lockup at all. In this circumstance, the relief device may open to prevent overpressurization in the regulator outlet. If this occurs on two or three of the lockup tests, the regulator would be marked as “failed”. Additionally, regulators that did not meet the UL 144 pressure relief criteria (for new regulators) in only one of three trials were not considered a failure. Often, for the older regulators, the start-to-discharge pressure in the initial trial was significantly higher than the subsequent trials indicating that the relief valve seat was stuck in place. The sticking of the relieve valve on older units was observed in a previous project on cylinder relief valves1. Once the pressure was high enough to overcome the adhesion force, the relief valve opened. As such, the remaining two trials relieved at much lower pressures because the relief valve seat was no longer stuck in place. These regulators were documented in the results tables but were not included in the “failure” tally. A summary of the test results for these failed regulators is shown in Table 15. Figures 72 through 75 provide the distribution of regulator failures (based on the causes listed above) compared to the number of regulators tested for the various regulator types, manufacturers, ages, and environmental conditions. Exact numbers are provided in Tables 16 through 19.

1 Stephens,D.R., Gifford, D.R.,Francini R.B., Mooney, D.D., CG-7 Pressure Relief Valve and Propane Cylinder Performance,NPGA, January 2003.

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Performance, Durability, and Service Life of 83 September 2006 Low Pressure Propane Vapor Regulators Battelle

Tab

le 1

5. S

umm

ary

tabl

e of

faile

d re

gula

tors

.

Regu

lato

r ID

Reg

ulat

or

Man

ufac

ture

r:R

egul

ator

Ty

peR

egul

ator

Ag

e (y

ears

)C

limat

eR

egul

ator

Lo

catio

n St

ate

Serv

ice

Area

Reas

on fo

r Reg

ulat

or R

emov

alEx

tern

al

Visu

al

Insp

ectio

n

Inte

rnal

In

spec

tion

and

Adju

stm

ent

Mod

erat

e In

let

Pres

sure

Low

Inle

t Pr

essu

reHi

gh In

let

Pres

sure

Star

t-to-

Disc

harg

e Pr

essu

re

Res

eatin

g Pr

essu

re

50M

anuf

actu

rer B

1st S

tage

9C

ool,

Dam

pW

ASu

burb

anFa

ulty

regu

lato

rO

XLe

akin

g th

roug

h cr

imp

in re

gula

tor b

ody

95M

anuf

actu

rer A

1st S

tage

28C

ool,

Dry

SDR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OTo

ok 1

5-m

in to

atta

in 1

0 ps

ig o

utle

t pre

ssur

e

120

Man

ufac

ture

r A1s

t Sta

ge10

Coo

l, D

ryO

HR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OX

Leak

ed th

roug

h PR

D d

urin

g ad

just

men

t

247

Man

ufac

ture

r B1s

t Sta

ge8

Coo

l, D

rySD

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

OO

OO

OX

PRD

rese

ated

at 1

2.67

psi

258

Man

ufac

ture

r B1s

t Sta

ge32

Coo

l, D

ryIA

Rur

alEn

d of

man

ufac

ture

r's re

com

men

ded

serv

ice

life

OO

utle

t pre

ssur

e w

ould

not

sta

biliz

e du

ring

adju

stm

ent

267

Man

ufac

ture

r B1s

t Sta

ge41

Coo

l, D

ryIA

Rur

alEn

d of

man

ufac

ture

r's re

com

men

ded

serv

ice

life

OO

utle

t pre

ssur

e w

ould

not

sta

biliz

e du

ring

adju

stm

ent

275

Man

ufac

ture

r A1s

t Sta

ge47

Coo

l, D

ryIA

Rur

alEn

d of

man

ufac

ture

r's re

com

men

ded

serv

ice

life

OX

Leak

thro

ugh

regu

lato

r; st

oppe

d te

st a

t 27

psig

out

let p

ress

ure

280

Man

ufac

ture

r A1s

t Sta

ge46

Coo

l, D

ryIA

Rur

alEn

d of

man

ufac

ture

r's re

com

men

ded

serv

ice

life

ΔΔ

OO

XR

egul

ator

is ru

sty;

slo

w lo

ck-u

p; le

aked

thro

ugh

regu

lato

r dur

ing

high

pre

ssur

e lo

ck-u

p te

st (2

50 p

sig)

321

Man

ufac

ture

r B1s

t Sta

ge57

Coo

l, D

rySD

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

Low

out

let p

ress

ures

eve

n w

ith a

djus

tmen

t all

the

way

ope

n

361

Man

ufac

ture

r B1s

t Sta

ge27

War

m, D

ryC

AU

rban

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

ΔΔ

OO

OX

XAd

just

ing

scre

w a

ll th

e w

ay d

own;

Low

relie

f and

rese

atin

g pr

essu

res

(10.

92

psig

and

10.

71 p

sig,

resp

ectiv

ely)

440

Man

ufac

ture

r B1s

t Sta

ge6

War

m, D

rySC

Rur

alO

ther

OO

OO

OO

XLo

w re

seat

ing

pres

sure

s (1

3.7

psi)

449

Man

ufac

ture

r B1s

t Sta

ge7

War

m, D

ryVA

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

OO

OX

Cha

tters

and

leak

s th

roug

h PR

D d

urin

g hi

gh p

ress

ure

lock

-up

test

(250

psi

g in

let)

460

Man

ufac

ture

r B1s

t Sta

ge41

War

m, D

ryVA

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

Out

let p

ress

ure

wou

ld n

ot s

tabi

lize

durin

g ad

just

men

t; ad

just

ing

nut f

roze

n in

pl

ace

461

Man

ufac

ture

r B1s

t Sta

ge46

War

m, D

ryVA

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

XC

hatte

rs a

nd le

aks

thro

ugh

PRD

dur

ing

adju

stm

ent

487

Man

ufac

ture

r A1s

t Sta

ge25

Coo

l, D

amp

INR

ural

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

Cou

ld n

ot a

djus

t reg

ulat

or; l

ocke

d in

pla

ce

538

Man

ufac

ture

r A1s

t Sta

ge16

War

m, D

ryPA

Subu

rban

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OO

-X

Star

ted

to le

ak th

roug

h PR

V at

0 c

fh a

nd 2

5 ps

ig in

let;

Max

lock

-up

= 14

.97

psi.

559

Man

ufac

ture

r B1s

t Sta

ge49

Coo

l, D

amp

INR

ural

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

OO

OO

utle

t pre

ssur

e w

ould

not

sta

biliz

e du

ring

lock

-up

test

ing

563

Man

ufac

ture

r A1s

t Sta

ge28

Coo

l, D

amp

INR

ural

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

Cou

ld n

ot a

djus

t reg

ulat

or; l

ocke

d in

pla

ce

565

Man

ufac

ture

r B1s

t Sta

ge16

Coo

l, D

amp

MI

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

OO

OX

Cha

tters

and

leak

s th

roug

h re

gula

tor a

t 250

psi

g in

let p

ress

ure

and

80 c

fh

571

Man

ufac

ture

r B1s

t Sta

ge10

Coo

l, D

amp

MI

Rur

alFa

ulty

regu

lato

rO

XLe

aked

thro

ugh

PRD

dur

ing

adju

stm

ent

615

Man

ufac

ture

r B1s

t Sta

ge15

Coo

l, D

ryIA

Rur

alFa

ulty

regu

lato

rO

OO

OO

XLe

ak a

roun

d PR

D fl

ange

617

Man

ufac

ture

r B1s

t Sta

ge10

Coo

l, D

ryIA

Rur

alFa

ulty

regu

lato

r: le

aked

OO

OO

OX

XLo

w re

lief a

nd re

seat

ing

pres

sure

s (1

3.97

psi

g an

d 13

.88

psig

, res

pect

ivel

y)

656

Man

ufac

ture

r B1s

t Sta

ge4

Coo

l, D

ryN

YU

rban

Oth

er: r

eloc

ated

tank

, cha

nged

regs

OO

OO

OX

XLo

w re

lief a

nd re

seat

ing

pres

sure

s (1

0.9

psig

and

10.

8 ps

ig, r

espe

ctiv

ely)

718

Man

ufac

ture

r A1s

t Sta

ge27

Coo

l, D

ryIA

Rur

alEn

d of

man

ufac

ture

r's re

com

men

ded

serv

ice

life

OO

XC

hatte

rs a

nd le

aks

thro

ugh

PRD

at 8

0 cf

h an

d 10

0 ps

ig in

let p

ress

ure

783

Man

ufac

ture

r B1s

t Sta

ge14

War

m, D

amp

MS

Faul

ty re

gula

tor

OO

utle

t pre

ssur

e w

ould

not

sta

biliz

e; p

ress

ure

cont

inue

d to

clim

b at

100

psi

g in

let p

ress

ure

and

80 c

fh

22M

anuf

actu

rer B

2nd

Stag

e41

War

m, D

amp

MO

Rur

alFa

ulty

regu

lato

rO

ΔX

Leak

thro

ugh

regu

lato

r at 1

0 ps

ig in

let p

ress

ure

and

0 cf

h (lo

ck-u

p)30

Man

ufac

ture

r B2n

d St

age

15C

ool,

Dry

IAR

ural

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

OO

OO

XO

Max

sta

rt-to

-dis

char

ge p

ress

ure

= 36

.3" W

.C.

33M

anuf

actu

rer B

2nd

Stag

e15

Coo

l, D

ryIA

Urb

anEn

d of

man

ufac

ture

r's re

com

men

ded

serv

ice

life

OAd

just

men

t all

the

way

dow

n; lo

w o

utle

t pre

ssur

e (8

.6" W

.C.)

48M

anuf

actu

rer B

2nd

Stag

e3

Coo

l, D

amp

WA

Rur

alFa

ulty

regu

lato

rO

XLe

aked

thro

ugh

PRD

dur

ing

adju

stm

ent

52M

anuf

actu

rer B

2nd

Stag

e10

Coo

l, D

amp

WA

Subu

rban

Faul

ty re

gula

tor

XLe

aked

thro

ugh

regu

lato

r at 1

0 ps

ig in

let a

nd 0

.5 c

fh60

Man

ufac

ture

r A2n

d St

age

37W

arm

, Dry

MS

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

OO

OO

XO

Max

sta

rt-to

-dis

char

ge p

ress

ure

= 34

.5" W

.C.

68M

anuf

actu

rer B

2nd

Stag

e13

Coo

l, D

amp

OH

Subu

rban

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OO

OO

XO

Max

Loc

k-up

= 1

3.5"

W.C

.; M

ax s

tart-

to-d

isch

arge

pre

ssur

e =

47.2

" W.C

.

71M

anuf

actu

rer A

2nd

Stag

e2

Coo

l, D

ryC

OR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OX

Bad

leak

thro

ugh

adju

stin

g sc

rew

72M

anuf

actu

rer A

2nd

Stag

e16

Coo

l, D

ryC

OR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OX

Cha

tters

and

leak

s th

roug

h PR

D a

t 30

cfh

and

10 p

sig

inle

t11

7M

anuf

actu

rer A

2nd

Stag

e9

War

m, D

ryO

HR

ural

OX

Leak

s th

roug

h PR

D a

t 30

cfh

and

10 p

sig

inle

t12

4M

anuf

actu

rer A

2nd

Stag

e16

War

m, D

amp

NC

Rur

alEn

d of

man

ufac

ture

r's re

com

men

ded

serv

ice

life

XLe

ak th

roug

h re

gula

tor a

t 10

psig

inle

t and

0 c

fh (l

ock-

up)

130

Man

ufac

ture

r B2n

d St

age

17W

arm

, Dam

pN

CSu

burb

anEn

d of

man

ufac

ture

r's re

com

men

ded

serv

ice

life

ΔΔ

OO

OX

OM

ax s

tart-

to-d

icha

rge

pres

sure

= 3

4.4"

W.C

.

168

Man

ufac

ture

r A2n

d St

age

10W

arm

, Dam

pM

SR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

ΔX

Leak

s th

roug

h PR

D a

t 30

cfh

and

10 p

sig

inle

t; ve

nt s

cree

n m

issi

ng

170

Man

ufac

ture

r A2n

d St

age

22W

arm

, Dry

KYSu

burb

anEn

d of

man

ufac

ture

r's re

com

men

ded

serv

ice

life

ΔO

OO

OX

OIn

let f

ittin

g ru

sty

and

diffi

cult

to re

mov

e; M

ax s

tart-

to-d

icha

rge

pres

sure

= 3

5.5"

W

.C.

191

Man

ufac

ture

r B2n

d St

age

48W

arm

, Dam

pM

SR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OX

Leak

ed th

roug

h PR

D d

urin

g ad

just

men

t

221

Man

ufac

ture

r A2n

d St

age

15C

ool,

Dam

pM

IR

ural

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

OO

OO

XO

Inle

t fitt

ing

rust

y an

d di

fficu

lt to

rem

ove;

Max

sta

rt-to

-dic

harg

e pr

essu

re =

35.

6"

W.C

.25

5M

anuf

actu

rer B

2nd

Stag

e32

Coo

l, D

ryIA

Rur

alEn

d of

man

ufac

ture

r's re

com

men

ded

serv

ice

life

OO

OO

OX

OM

ax s

tart-

to-d

isch

arge

pre

ssur

e =

60.1

" W.C

. dur

ing

the

trial

1

256

Man

ufac

ture

r B2n

d St

age

40C

ool,

Dry

IAR

ural

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

ΔX

Dirt

y in

side

regu

lato

r; Le

ak th

roug

h re

gula

tor a

t 10

psig

inle

t and

0 c

fh; M

ax

Lock

-up

= 15

.7" W

.C.

263

Man

ufac

ture

r A2n

d St

age

41C

ool,

Dry

IAR

ural

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

OO

OO

XO

Max

sta

rt-to

-dis

char

ge p

ress

ure

= 33

.5" W

.C.

268

Man

ufac

ture

r A2n

d St

age

32C

ool,

Dry

IAR

ural

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

OO

OO

XO

Reg

ulat

or b

olts

ver

y ru

sty;

Max

sta

rt-to

-dic

harg

e pr

essu

re =

42.

6" W

.C.

345

Man

ufac

ture

r A2n

d St

age

4W

arm

, Dry

KYR

ural

Oth

erO

O-

+O

XO

Max

Loc

k-up

= 1

3.9"

W.C

.; M

ax s

tart-

to-d

isch

arge

pre

ssur

e =

41.8

" W.C

.36

7M

anuf

actu

rer B

2nd

Stag

e39

War

m, D

amp

WA

Urb

anTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

OO

OO

XO

Max

sta

rt-to

-dis

char

ge p

ress

ure

= 59

" W.C

.

445

Man

ufac

ture

r B2n

d St

age

6W

arm

, Dry

SCR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OO

OO

OX

OM

ax s

tart-

to-d

isch

arge

pre

ssur

e =

34" W

.C.

479

Man

ufac

ture

r A2n

d St

age

30C

ool,

Dry

WI

Rur

alEn

d of

man

ufac

ture

r's re

com

men

ded

serv

ice

life

OX

Reg

ulat

or c

hatte

rs a

nd le

aks

thro

ugh

PRD

at 3

0 cf

h an

d 10

psi

g in

let

502

Man

ufac

ture

r B2n

d St

age

20C

ool,

Dry

IAR

ural

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

OO

OO

XO

Max

sta

rt-to

-dis

char

ge p

ress

ure

= 35

.2" W

.C.

514

Man

ufac

ture

r A2n

d St

age

11W

arm

, Dam

pVA

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

OO

OO

OX

Low

rese

atin

g pr

essu

res

(11.

8" W

.C.)

530

Man

ufac

ture

r B2n

d St

age

25C

ool,

Dam

pPA

Subu

rban

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

OO

OO

XO

Max

sta

rt-to

-dis

char

ge p

ress

ure

= 34

.2" W

.C.

550

Man

ufac

ture

r B2n

d St

age

22C

ool,

Dam

pIN

Rur

alEn

d of

man

ufac

ture

r's re

com

men

ded

serv

ice

life

OO

OX

OVe

ry ru

sty;

Max

sta

rt-to

-dis

char

ge p

ress

ure

= 35

.7" W

.C.

556

Man

ufac

ture

r A2n

d St

age

34C

ool,

Dam

pIN

Rur

alEn

d of

man

ufac

ture

r's re

com

men

ded

serv

ice

life

OO

OO

OX

OM

ax s

tart-

to-d

isch

arge

pre

ssur

e =

44.5

" W.C

.

711

Man

ufac

ture

r A2n

d St

age

27C

ool,

Dry

SDR

ural

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

OO

OO

XPR

D d

id n

ot re

lieve

eve

n af

ter i

ncre

asin

g pr

essu

re to

65"

W.C

.

38M

anuf

actu

rer A

Sing

le37

Coo

l, D

ryIA

Rur

alEn

d of

man

ufac

ture

r's re

com

men

ded

serv

ice

life

OAd

just

ing

sprin

g fro

zen;

low

out

let p

ress

ures

55M

anuf

actu

rer A

Sing

le15

War

m, D

ryKS

Rur

alC

hang

ed fr

om s

ingl

e to

dua

l reg

ulat

or s

yste

mO

XLe

aks

thro

ugh

PRD

at 3

0 cf

h an

d 10

0 ps

ig in

let

67M

anuf

actu

rer A

Sing

le27

Coo

l, D

amp

OH

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

OO

OO

XO

Max

sta

rt-to

-dis

char

ge =

35.

4" W

.C.

81M

anuf

actu

rer A

Sing

le13

Coo

l, D

rySD

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

ΔX

Reg

ulat

or c

hatte

rs; l

eaks

thro

ugh

PRD

at h

igh

flow

rate

s; s

-t-d

= 10

.2" W

.C.

85M

anuf

actu

rer A

Sing

le20

Coo

l, D

rySD

Rur

alTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

ΔX

OX

Leak

thro

ugh

regu

lato

r; M

ax L

ock-

up =

17.

8" W

.C.;

leak

s th

roug

h PR

D a

t hig

h flo

w ra

te (8

0 cf

h); s

-t-d

= 13

.7" W

.C.

181

Man

ufac

ture

r ASi

ngle

23W

arm

, Dam

pM

SR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OC

ould

not

adj

ust r

egul

ator

dow

n to

11"

W.C

.

193

Man

ufac

ture

r BSi

ngle

42W

arm

, Dam

pM

SR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OC

ould

not

adj

ust r

egul

ator

dow

n to

11"

W.C

.

197

Man

ufac

ture

r ASi

ngle

18W

arm

, Dry

MS

Rur

alEn

d of

man

ufac

ture

r's re

com

men

ded

serv

ice

life

XO

OM

ax L

ock-

up =

20.

0" W

.C.;

Reg

ulat

or c

hatte

red

and

leak

ed th

roug

h th

e PR

D

at 1

00 p

sig

& 80

cfh

then

sto

pped

; PR

D m

ax s

tart-

to-d

isch

arge

= 3

9.2"

W.C

.

199

Man

ufac

ture

r ASi

ngle

15W

arm

, Dry

MS

Rur

alEn

d of

man

ufac

ture

r's re

com

men

ded

serv

ice

life

ΔAd

just

ing

scre

w a

ll th

e w

ay d

own;

low

out

let p

ress

ures

; Inl

et th

read

s ru

sty

201

Man

ufac

ture

r ASi

ngle

40W

arm

, Dry

MS

Rur

alEn

d of

man

ufac

ture

r's re

com

men

ded

serv

ice

life

XLe

ak th

roug

h re

gula

tor;

Max

Loc

k-up

= 1

9" W

.C.

203

Man

ufac

ture

r ASi

ngle

11*

War

m, D

ryM

SR

ural

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

Adju

stin

g sc

rew

all

the

way

dow

n; lo

w o

utle

t pre

ssur

es

238

Man

ufac

ture

r BSi

ngle

55C

ool,

Dry

SDR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

XLe

ak th

roug

h re

gula

tor;

Max

Loc

k-up

= 3

4.4"

W.C

.

292

Man

ufac

ture

r ASi

ngle

27C

ool,

Dry

SDR

ural

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

ΔΔ

OO

XO

Pres

sure

relie

f scr

een

mis

sing

; slo

w lo

ck-u

p; M

ax s

tart-

to-d

isch

arge

= 3

3.9"

W

.C.;

Max

lock

-up

= 18

" W.C

.31

3M

anuf

actu

rer A

Sing

le16

War

m, D

ryM

SR

ural

End

of m

anuf

actu

rer's

reco

mm

ende

d se

rvic

e lif

eO

O-

--

XO

Max

sta

rt-to

-dis

char

ge =

43"

W.C

.; M

ax lo

ck-u

p =

23.3

" W.C

.35

3M

anuf

actu

rer A

Sing

le15

War

m, D

amp

MS

Rur

alEn

d of

man

ufac

ture

r's re

com

men

ded

serv

ice

life

OX

Reg

ulat

or c

hatte

rs; l

eaks

thro

ugh

PRD

at 3

0 cf

h

358

Man

ufac

ture

r BSi

ngle

28W

arm

, Dry

CA

rura

lEn

d of

man

ufac

ture

r's re

com

men

ded

serv

ice

life

OX

Reg

ulat

or c

hatte

rs; l

eaks

thro

ugh

PRD

at 3

0 cf

h

360

Man

ufac

ture

r BSi

ngle

50W

arm

, Dry

CA

rura

lEn

d of

man

ufac

ture

r's re

com

men

ded

serv

ice

life

OX

Reg

ulat

or c

hatte

rs; l

eaks

thro

ugh

PRD

at 3

0 cf

h36

2M

anuf

actu

rer B

Sing

le13

War

m, D

ryC

Aru

ral

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OR

egul

ator

out

let p

ress

ure

will

not h

old

stea

dy

397

Man

ufac

ture

r ASi

ngle

23W

arm

, Dry

AZru

ral

Cha

nged

from

sin

gle

to d

ual r

egul

ator

use

Reg

ulat

or w

ill no

t loc

k-up

; max

pre

ssur

e be

fore

test

sto

pped

= 1

9.7"

W.C

.40

0M

anuf

actu

rer A

Sing

le16

War

m, D

rySC

rura

lO

ΔX

Reg

ulat

or le

aked

thro

ugh

PRD

at 3

0 cf

h

407

Man

ufac

ture

r ASi

ngle

12W

arm

, Dry

SCur

ban

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OO

-O

OX

OM

ax L

ock-

up =

13.

8" W

.C.;

Max

sta

rt-to

-dis

char

ge =

33.

3" W

.C.

18M

anuf

actu

rer B

Inte

gral

2-

stag

e7

Coo

l, D

amp

WA

Urb

anTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

ΔX

Leak

thro

ugh

PRD

at 1

00 p

sig

inle

t pre

ssur

e an

d hi

gh fl

ow ra

te (8

0 cf

h)54

Man

ufac

ture

r ATw

in s

tage

7W

arm

, Dry

KSR

ural

Faul

ty re

gula

tor

-O

XLe

ak th

roug

h re

gula

tor;

Max

Loc

k-up

= 1

7" W

.C.;

PRD

did

not

ven

t

106

Man

ufac

ture

r BIn

tegr

al 2

-St

a ge

11C

ool,

Dam

pAK

Rur

alFa

ulty

regu

lato

rO

OO

OO

XO

Max

sta

rt-to

-dis

char

ge p

ress

ure

= 33

.7" W

.C.

107

Man

ufac

ture

r BIn

tegr

al 2

-St

age

13C

ool,

Dam

pAK

Rur

alFa

ulty

regu

lato

rO

ΔX

Leak

thro

ugh

regu

lato

r at 1

00 p

sig

inle

t pre

ssur

e an

d 0

cfh

(lock

-up)

; Max

Lo

ck-u

p =

30.9

" W.C

.

116

Man

ufac

ture

r BIn

tegr

al 2

-St

age

10C

ool,

Dam

pW

ASu

burb

anO

ther

OX

Leak

s th

roug

h PR

D a

t 30

cfh

and

100

psig

inle

t pre

ssur

e

340

Man

ufac

ture

r BTw

in S

tage

10C

ool,

Dam

pW

ASu

burb

anTa

nk a

nd re

gula

tor r

emov

ed fr

om s

ervi

ce a

t loc

atio

nO

ΔO

XLe

aks

thro

ugh

regu

lato

r whe

n ad

just

ing

from

80

cfh

to 3

0 cf

h at

100

psi

g an

d 25

psi

g in

let p

ress

ures

347

Man

ufac

ture

r BIn

tegr

al 2

-St

a ge

13C

ool,

Dam

pAK

Rur

alFa

ulty

regu

lato

rO

OO

OX

Star

ted

to le

ak th

roug

h th

e pr

essu

re re

lief a

t 250

psi

g in

let p

ress

ure

475

Man

ufac

ture

r BC

ombo

11W

arm

, Dry

NJ

Subu

rban

Tank

and

regu

lato

r rem

oved

from

ser

vice

at l

ocat

ion

OX

Reg

ulat

or le

aks

thro

ugh

PRD

at 3

0 cf

h an

d 10

0 ps

ig in

let

476

Man

ufac

ture

r BC

ombo

13W

arm

, Dry

NJ

Urb

anEn

d of

man

ufac

ture

r's re

com

men

ded

serv

ice

life

OO

OO

XLe

aks

thro

ugh

PRD

at 0

.5 c

fh a

nd 2

50 p

sig

inle

t

490

Man

ufac

ture

r BIn

tegr

al 2

-St

age*

*6

War

m, D

amp

FLSu

burb

anC

hang

ed fr

om s

ingl

e to

dua

l reg

ulat

or s

yste

mO

XR

egul

ator

cha

tters

; lea

ks th

roug

h PR

D a

t 30

cfh

and

100

psig

inle

t

637

Man

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Table 16. Regulator failures by type.

Reason for Failure 1st

Stage 2nd

Stage Integral

Two-Stage Single-stage Total

Chatters and leaks through regulator PRD 9 10 8 10 37 Leak in regulator body 2 1 3 PRD start-to discharge and/or reseat pressure too low

5 1 6

PRD start-to discharge pressure too high 16 2 4 22 Outlet pressure will not stabilize 9 1 7 17 PRD did not relieve 1 1 2

Total 25 30 11 21 87 Total Tested 111 102 21 32 266

% Failed in Group 22.5% 29.4% 52.4% 65.6%

21 out of 32

11 out of 21

30 out of 102

25 out of 111

0.0%

10.0%

20.0%

30.0%

40.0%

50.0%

60.0%

70.0%

80.0%

90.0%

100.0%

1st S

tage

2nd

Sta

ge

Inte

gral

2-

Sta

ge

Sin

gle

Sta

ge

% o

f Spe

cim

ens

% Failed in Group

Figure 73. Regulator “failures” by type of regulator.

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Table 17. Regulator failures by manufacturer.

Reason for Failure Manuf. A Manuf. B Other Total

Chatters and leaks through regulator PRD 17 20 37 Leak in regulator body 1 2 3 PRD start-to discharge and/or reseat pressure too low 1 5 6 PRD start-to discharge pressure too high 11 11 22 Outlet pressure will not stabilize 8 9 17 PRD did not relieve 2 0 2

Total 40 47 0 87 Total Tested 139 127 0 266

% Failed in Group 28.8% 37.0% 0%

40 out of 139

47 out of 127

0/20.0%

10.0%

20.0%

30.0%

40.0%

50.0%

60.0%

70.0%

80.0%

90.0%

100.0%

Manufacturer A Manufacturer B Other

% o

f Spe

cim

ens

% Failed in Group

Figure 73. Regulator “failures” by regulator manufacturer.

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Table 18. Regulator failures by age.

Reason for Failure 0-5 6-10 11-15 16-20 21-25 26-30 31-35 36-40 41-45 46-50 51-55 56-60 Total

Chatters and leaks through regulator PRD

1 9 7 8 3 2 1 5 1 37

Leak in regulator body 1 1 1 3 PRD start-to discharge and/or reseat pressure too low

1 3 1 1 6

PRD start-to discharge pressure too high

1 1 5 3 3 3 3 2 1 22

Outlet pressure will not stabilize

5 3 2 1 1 3 1 1 17

PRD did not relieve 1 1 2

Total 4 15 19 11 6 10 4 5 5 6 1 1 87

Total Tested 29 49 50 37 20 23 15 11 15 12 2 1 266*

% Failed in Group 13.8 30.6 38.0 29.7 30.0 43.5 26.7 45.5 33.3 50.0 50.0 100

*Two regulators of unknown age in the test sample; however, neither failed the test criteria.

0/20/0

4/29

15/49

19/50

11/37 6/20

10/23

4/15

5/11

5/15

6/12 1/2

1/1

0.0%

10.0%

20.0%

30.0%

40.0%

50.0%

60.0%

70.0%

80.0%

90.0%

100.0%

0-5

6-10

11-1

5

16-2

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5

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0

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5

46-5

0

51-5

5

55-6

0

60-6

5

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now

n

% o

f Spe

cim

ens

% Failed in Group

Figure 74. Regulator “failures” by regulator age.

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Table 19. Regulator failures by environmental condition.

Reason for Failure Warm,

Dry Warm, Damp

Cool, Dry

Cool, Damp Total

Chatters and leaks through regulator PRD 12 6 10 9 37 Leak in regulator body 2 1 3 PRD start-to discharge and/or reseat pressure too low

2 1 3 6

PRD start-to discharge pressure too high 7 2 6 7 22 Outlet pressure will not stabilize 5 3 6 3 17 PRD did not relieve 1 1 2

Total 27 12 28 20 87

Total Tested 59 46 98 63 266

% Failed in Group 45.8% 26.1% 28.6% 31.7%

20 out of 6328 out of 98

12 out of 46

27 out of 59

0.0%

10.0%

20.0%

30.0%

40.0%

50.0%

60.0%

70.0%

80.0%

90.0%

100.0%

Warm, Dry Warm, Damp Cool, Dry Cool, Damp

% o

f Spe

cim

ens

% Failed in Group

Figure 75. Regulator “failures” by type of environment.

The percentage of failures for all categories ranged from a low of 14% in the 0 to 5-year age range to a high of 100% in the 55 to 60-year age range. A majority of the categories had failure rates around 30% with regulators from warm, dry regions and regulators above the age of 45 having approximately a 50% failure rate. Integral two-stage regulators had failure rates over 50% and single-stage regulators had failure rates near 65%.

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The largest cause of regulator failure, with 37 regulators that failed, was regulators that chattered and leaked through the PRD. The second largest cause of regulator failure, with 22 regulators that failed, was regulators with PRD start-to-discharge pressures that were too high. Both these failure mechanisms possibly indicate that the conditions under which the regulators were tested may have been more severe than what is typically seen out in the field. A flowrate of 80 cfh is higher than a normal household application, and this high flowrate may have contributed to the failures identified in this study. Additionally, tank pressures of 250 psig, which would be the inlet pressure for first-stage, single-stage, and integral two-stage regulators, are not likely to occur and may have also stressed these regulators beyond the limits of normal operation. While these parameters were higher than would be experienced in normal operation, these maximums are not beyond the design specifications of new regulators.

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6.0 INSPECTIONS OF “FAILED” REGULATORS (TASK 3) Several of the regulators identified as “failures” were selected for detailed failure analysis to determine possible failure mechanisms and environmental variables that contributed to the failure. The failure analysis selection process was not intended to be statistically-based as was the testing selection process. The selection was subjective, and an attempt was made to select samples that had a range of reasons for not meeting the UL 144 performance requirements, a range of environmental conditions, a range of ages, and a balance of the two predominant manufacturers. The regulators selected for failure analysis are presented in Table 20 with detailed analyses provided in Appendix C.

Table 20. Regulators selected for failure analysis.

Regulator ID Manuf. Age Climate State

Service Area Reason for Removal

Reason for Not Meeting UL Criteria

13 (2-stage)

A 13 Warm, Damp

AL Rural Faulty regulator; no pressure at regulator

outlet

High lock-up pressure

42 (second)

B 16 Warm, Dry

IL Suburban End of manuf. recom. service life

High lock-up pressure

72 (second)

A 16 Cool, Dry

CO Rural Tank and regulator removed from

service

Chatters and leaks through PRD at 10 psig

inlet pressure and 30 cfh. 353

(single) A 15 Warm,

Damp MS Rural End of manuf.

recom. service life Chatters and leaks

through PRD at 100 psig inlet pressure and 30 cfh.

361 (first) B 27 Warm, Dry

CA Urban Tank and regulator removed from

service

PRD start-to-discharge and reseating pressures too low; dirty exterior;

clean interior; could not adjust

383 (single)

B 43 Cool, Dry

SD Rural PRD start-to-discharge pressure too high in first

trial; high lock-up 490

(2-stage) B 6 Warm,

Damp FL Suburban Changed from

single to dual regulator system

Chatters and leaks through PRD at 100 psig inlet pressure and 30 cfh.

538 (first) A 16 Warm, Dry

PA Suburban Tank and regulator removed from

service

Leak through PRD at 25 psi inlet pressure and 0

cfh; high lock-up pressure571 (first) B 10 Cool,

Damp MI Rural Faulty regulator Leaked through PRD

during adjustment 711

(second) A 27 Cool,

Dry SD Rural End of manuf.

recom. service life PRD did not relieve after

reaching 65” W.C. Findings from the failure analysis indicate a few possible trends as to why some regulators did not meet the test criteria. In particular, the second-stage regulator 711 did not relieve because of excessive dirt and spider webs blocking the relief opening (Figure 76). This is not a manufacturing issue but rather a maintenance or installation issue and would not be indicative of

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any problems related to regulator age, environment, or manufacturer. This problem is not expected for regulators that are properly inspected and maintained.

Figure 76. Regulator 711 — blocked pressure relief. For the regulators that were disassembled and analyzed, debris within the regulator body was the single most common potential cause for high regulator lock-up and/or leaks through the PRD (regulators 13, 72, 353, and 571). Some of the debris found appears to be corrosion products (from piping or containers), but other debris appears to be related to regulator manufacturing. For example, first-stage regulator 571 contained machining turnings inside the body of a regulator, with some pieces stuck on the control disk seat (Figure 77, circled). This debris was too large to get through the inlet screen of the regulator and appeared to be from the regulator manufacturing process.

Figure 77. Regulator 571 — machining turnings found inside regulator.

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Other regulators (42 and 383) showed some damage to the regulator seat disc which could have led to high lock-up pressures. For example, single-stage regulator 383 appeared to be in good condition during initial external and internal (visual through the bonnet opening) examinations. However, when examined more closely significant degradation of the seat disc was found (Figure 78). The seat disc appeared to have material losses more significant than what would be expected solely from the compression set. Compression set is the permanent deformation of an elastomer after it has been compressed for an extended period of time. In addition, a significant amount of debris was found between the orifice and seat disc which could be attributed to the material lost from the seat disc. While this degradation is significant, this regulator was 43 years old when removed from service. This unit was in service well beyond the recommended service life of either the 15-year period or the more recent periods of 20 or 25 years.

Figure 78. Regulator 383 — seat disc.

For several other regulators (361, 490, and 538) no specific cause for the regulator “failure” could be determined. Possible causes included a slash on the diaphragm and a scratch on the regulator shaft that mates with the o-ring seal, however all other locations within the regulator body appeared to be in working order and free from significant debris.

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7.0 CONCLUSIONS The objective of this program was to determine if there were bases for a recommended service life of 15 years for propane regulators. The program considered information gathered from the technical or manufacturers’ literature and from tests performed on a sample of regulators removed from service. Seven hundred seventy-three regulators were received from marketers across the United States, varying in age from less than one year to more than sixty years. A sample of 266 regulators was selected from the overall population received, and these 266 were tested to a protocol that was developed based on UL 144, Pressure-Regulating Valves for LP-Gas. Outlet pressures for two gas flow rates, lock-up pressures, PRD start-to-discharge pressures and PRD reseat pressures were measured on the tested regulators.

7.1 Literature Survey

A review of U.S. manufacturers’ literature found that three manufacturers have recently increased the recommended service life of their regulators from 15 years to 20 or 25 years (depending on the specific manufacturer). The manufacturers’ literature did not explicitly cite the reason for the increase in recommended service life, but the literature identified design features that influence service life, include corrosion resistant relief valve seats, stainless steel relief valve springs and retainers, and painted, heavy-duty zinc bodies and bonnets. One technical paper was found that directly considered aging effects on propane vapor regulators. The paper discussed a study of regulators in Korea, which showed that in general the safety devices of the low pressure regulators deviated from normal operation after a year of service and deviated from the discharge start and reset pressures of the new regulators. Testing of diaphragms from the propane regulators in the field found a loss of tensile strength and decreased range of motion after five years of service. Researchers suspect a hardening of the diaphragms due to leaching of plasticizers from rubber materials over time. The paper also discussed the testing of propane regulator springs, which found a loss in tensile strength after seven years of service. This study recommended a six-year service life. There is no evidence that this recommendation was implemented in Korea. It should be noted that none of the regulators tested were from U.S. manufacturers. However, the Korean study does raise the issue of the long-term effects of a propane operating environment has on elastomer and spring performance. Technical references were identified that discussed the leaching various constituents, such as plasticizers and extenders, from elastomeric components. References were also identified that discuss the compositional variability of propane in the U.S. The findings of the literature review suggest further research in the use and variability of plasticizers and extenders in the rubber composition of propane regulator components; the long-term effect a propane operating environment has on elastomer and spring performance; and the effect of propane contaminants and off-specification gas on propane regulator performance.

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7.2 Effects of Age on Regulator Performance

Age appears to have little effect on the performance of first-stage regulators, and only a slight effect on the performance of second-stage regulators. On the other hand, age appears to have a significant effect on the performance of single-stage regulators; however, the sample size for this group was much smaller than the other groups, and therefore the results are less statistically significant. Aside from the mechanical differences that provide the pressure control ranges of the three main types (first, second, and single-stage), these types have several components in common – flexible, elastomeric diaphragm, elastomeric seat disc, steel springs, and mechanical linkage. All regulator types use elastomers in similar functions (seals, diaphragms, seat discs), so degradation of the elastomers would affect all types of regulators. The single-stage unit must control over a larger pressure ratio. A first-stage regulator, with a design inlet pressure of 250 psi and a nominal outlet pressure of 10 psi, and a second-stage regulator, with a nominal inlet pressure of 10 psi and a nominal outlet pressure of 11 inches of water, each have a pressure controlling ratio of approximately 25 (inlet pressure ÷ outlet pressure). Single-stage regulators have a design inlet pressure of 250 psi and a nominal outlet pressure of 11 inches of water, which is a pressure controlling ratio of approximately 630. This wide pressure-control requirement may make the single-stage units more susceptible to elastomer degradation and any corrosion on the metallic linkage parts. The testing did identify some issues related to age. Some regulators also exhibited lock-up pressures beyond the limits specified in UL 144; however this result was not considered as a regulator failure. The belief is that even though the regulator is not functioning within the limits of a new regulator it may still be fit for service. Over time, the elastomer material in the seat disc is likely to permanently indent/deform from repeated opening and closing of the regulator. This permanent deformation of the seat disc may lead to a larger range in the regulator pressure performance curve but is not likely to lead to significant operational or safety issues. These regulators have been noted as such in the test results documentation. However, if the seat disc is permanently deformed to the point that it will not close, the regulator will exhibit very high lockup or may not lockup at all. In this circumstance, the relief device may open to prevent overpressurization in the regulator outlet. If this occurs on two or three of the lockup tests, the regulator was marked as “failed”. Additionally, regulators that did not meet the UL 144 pressure relief criteria (for new regulators) in only one of three trials were not considered a failure. Often, for the older regulators, the start-to-discharge pressure in the initial trial was significantly higher than the subsequent trials indicating that the relief valve seat was stuck in place. The sticking of the relieve valve on older units was observed in a previous project on cylinder relief valves. Once the pressure was high enough to overcome the adhesion force, the relief valve opened. As such, the remaining two trials relieved at much lower pressures because the relief valve seat was no longer stuck in place. These regulators were documented in the results tables but were not included in the “failure” tally.

In this study, the key observation is that the two-stage regulator systems currently used show no significant degradation during the 20- to 25-year period of service that is now standard.

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7.3 Effects of Manufacturer on Regulator Performance

The numbers of regulators tested were fairly evenly distributed between two manufacturers, “A” and “B”, with over 125 units tested from each manufacturer. The test data of lockup pressures, relief start-to-discharge pressures, and relief reseat pressures do not show a noticeable variation of the data points taken as a group (considering all regulators tested of one manufacturer), or in the variability of a particular regulator. This is a good indicator that there is no significant difference in the data between the manufacturers.

7.4 Effects of Environment on Regulator Performance

The test data were compared from the perspective of the four environmental regions: - Warm; dry ( > 53°F; < 73% humidity), - Warm; damp ( > 53°F; > 73% humidity), - Cool; dry (< 53°F; < 73% humidity), and - Cool; damp (< 53°F; > 73% humidity).

The source environment comparison shows fairly consistent behavior in pressure tests of lock-up, PRD start-to-discharge, and PRD reseat across each environment. However, when the failure rates for the four environmental conditions are compared, a higher percentage of failures is documented for regulators received from a warm, dry environment. With the number of samples being reasonably significant (much greater than ten units), the fact that nearly half of the warm, dry regulators failed to meet the test criteria is also significant. Although internal and external corrosion may be considered a significant failure mechanism, the drying effects on elastomeric components such as seals and the diaphragm may be more significant. As noted earlier, more research is needed to clarify the effects of propane and its constituents and contaminants on elastomers.

7.5 Inspections of “Failed” Regulators

For the regulators that were disassembled and analyzed, debris within the regulator body was the single most common potential cause for high regulator lock-up and/or leaks through the PRD. Some of the debris found appears to be corrosion products (from piping or containers), but other debris appears to be related to regulator manufacturing. Other regulators showed some damage to the regulator seat disc that could have led to high lock-up pressures. For several other regulators no specific cause for the regulator “failure” could be determined. Possible causes included a slash on the diaphragm and a scratch on the regulator shaft that mates with the o-ring seal; however, all other locations within the regulator body appeared to be in working order and free from significant debris.

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APPENDIX A

Literature Review of Low Pressure Propane Vapor Regulators by GTI

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LITERATURE REVIEW

OF

U.S. LOW PRESSURE, PROPANE VAPOR REGULATORS

GTI# 20132.1.01/ PERC Docket 11073

Prepared for:

Propane Education and Research Council (PERC)

1140 Connecticut Ave., NW, Suite 1075

Washington DC 20036

November 2005

Gas Technology Institute 1700 S. Mount Prospect Rd. Des Plaines, Illinois 60018 www.gastechnology.org

ENERGY UTILIZATION CENTER

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ii

[Intentionally Blank]

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Literature Review of Regulator Service Life

iii

LEGAL NOTICE: This report was prepared by the Gas Technology Institute as an account of work sponsored by Propane Education and Research Council (PERC). Neither PERC nor any person acting on their behalf:

a. Makes any warranty or representation, express or implied, with respect to the accuracy, completeness or usefulness of the information contained in this report, or that the use of any information, apparatus, method, or process disclosed in this report may not infringe privately owned rights; or

b. Assumes any liability with respect to the use of, or for any and all damages resulting from the use of, any information, apparatus, method or process disclosed in this report.

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Table of Contents

Summary Findings .............................................................................................................. 1

Overview............................................................................................................................. 3 Background..................................................................................................................... 3 Objective......................................................................................................................... 3 Approach......................................................................................................................... 3

Literature Search Results .................................................................................................... 4 Elastomers....................................................................................................................... 4 Metals.............................................................................................................................. 6 Propane Composition...................................................................................................... 7 Codes & Standards Review ............................................................................................ 9 US Regulator Manufacturing Literature Review.......................................................... 12 Fisher Regulators .......................................................................................................... 13 RegO® Regulators......................................................................................................... 19 Sherwood Regulators.................................................................................................... 25

Conclusions....................................................................................................................... 31

References......................................................................................................................... 32

Tables

Table 1 GPA Liquefied Petroleum Gas Specifications....................................................... 7

Table 2 Typical Trace Contaminants Found in LP-Gas ..................................................... 8

Table 3 Fisher LP-Gas Regulators.................................................................................... 13

Table 4 Fisher Propane Regulator Service/Safety Bulletins............................................. 16

Table 5 RegO® LP-Gas Regulators................................................................................... 19

Table 6 Component Materials by RegO® Regulator Series.............................................. 20

Table 7 Component Materials by RegO® Regulator Series.............................................. 20

Table 8 RegO® Propane Regulator Service/Safety Literature Search Results ................. 22

Table 9 Sherwood LP-Gas Regulators.............................................................................. 25

Table 10 Sherwood Propane Regulator Service/Safety Bulletins..................................... 28

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Summary Findings Two propane regulator manufacturers have extended the service-life recommendation of some propane regulators, and a third manufacturer is contemplating the same. A literature review was important to determine if there was scientific or engineering support for a 15-year replacement recommendation.

• The literature review was not able to document scientific or engineering support for a service-life recommendation of 15-years or greater. The findings of the literature review warrant further research in the use and variability of plasticizers and extenders in the rubber composition of LPG regulator components; the long-term effect a propane operating environment has on elastomer and spring performance; and the effect of LP-Gas contaminants and off-specification gas on U.S. LPG regulator performance.

• In “Aging Characteristics of Low Pressure LPG Regulators for Domestic Use”, (Kim, Kwon 1999) results showed that in general the safety devices of the low-pressure regulators deviated from normal operation after a year of service and deviated from the discharge start and reset pressures of the new regulators. Overall, the operating and closing pressures also deviated from the pressure range of the new regulators after a year of service. A 6 year service life was determined:

- Testing of diaphragms from the LPG regulators in the field found a loss of tensile strength and decreased range of motion after 5 years of service. Researchers suspect a hardening of the diaphragms due to leaching of plasticizers from rubber materials over time. The authors called for further research to improve diaphragm durability and reliability, to investigate the effect of plasticizer extraction from rubber materials on diaphragm performance, and the development of new rubber materials with improved rubber characteristics and properties.

- Testing of LPG regulator springs from the field found a loss in tensile strength after a 7 year service life. The authors called for spring research on the length of the freedom field of the spring, the surface treatment on the ending parts of the spring, quality control in the manufacturing, and reinforcement of durability characteristics.

- None of the regulators tested were from U.S. manufacturers. Research is warranted to investigate the long-term effect a propane operating environment has on elastomer and spring performance.

• A review of elastomers reference literature, “The Vanderbilt Rubber Handbook -13th Edition”, (Ohm, 1990), and “Rosato’s Plastics Encyclopedia and Dictionary” (Rosato, 1993), found that additives, particularly plasticizers and extenders, can leach out over time, resulting in physical changes in size, elongation, and tear strength. In regulators, elastomers are used in valve seat discs and diaphragms. Research is warranted to assess the use and variability of plasticizers and extenders in the rubber composition of LPG regulator components.

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• In “Investigation of Portable or Handheld Devices for Detecting Contaminants” (Hutzler, Johnson 2005), findings indicate that while LP-Gas for domestic use meets commercial grade specifications, contamination occurs in small quantities in the supply chain over time. Further, the impact of propane contaminants and off-specification gas is not well documented. Research is warranted to investigate the effect of LP-Gas contaminants and off-specification gas on U.S. LPG regulator performance.

• Underwriters Laboratories’ UL 144 LP-Gas Regulators is the current performance standard for LP-Gas regulators and is designed for new regulators, not regulators that have been in the field. UL 144 is silent on the issue of service or useful life. Test requirements for materials in UL 144 are found in American Society of Testing and Materials (ASTM) standards that are designed to be an indicator of long-term performance.

• Codes and standards that reference UL 144, including NFPA 54: National Fuel Gas Code, NFPA 58: Liquid Petroleum Gas Code and ANSI Z21.18a-2001/CSA 6.3a Gas Appliance Pressure Regulators are silent on useful or service life of LPG system components.

• A review of U.S. manufacturers’ literature found: - RegO® recommends regulator service life of 25 yrs for regulators (except single-

stage) manufactured after 1995; all other regulators have a service life of 15 years. - Fisher recommends regulator replacement at 20 years, or over 15 years of age for

regulators that have experienced conditions (corrosion, underground systems, flooding, etc.) that would shorten their service life.

- Sherwood recommends regulator replacement after 15 years; however, in email correspondence with a Sherwood representative, a 25 year life on some models was quoted.

• Typical materials identified in the literature that are used in LPG regulators include zinc or die cast aluminum bodies, chromate coatings, nitrile rubber and other synthetic polymers, and stainless steel springs.

• Service life attributes, or manufacturers’ stated features that influence service life, include corrosion resistance coatings and stainless steel relief valve spring and retainer, and a corrosion resistant relief valve seat (Fisher); stainless steel relief valve spring and retainer (Fisher); and painted, heavy-duty zinc (body and bonnet) resists corrosion and gives long-life protection, even under “salty air” conditions. (RegO®).

• All three manufacturers’ literature reference National Propane Gas Association (NPGA) documents in discussions related to installation, inspection, maintenance, and safety. NPGA no longer supports these documents and has released these documents to the public domain provided that they are not attributed to NPGA. Discontinued documents that are referenced include: - NPGA Installation and Service Guide Book #4003, - NPGA Propane Safety and Technical Support Manual Bulletin T403, - NPGA Safety Pamphlet 306 “LP-Gas Regulator and Valve Inspection and

Maintenance”,

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- NPGA LPG Safety Handbook #0001, and - NPGA Bulletin #133-80. These documents can no longer be referenced as NPGA documents and effort should be made by the manufacturers to acknowledge and correct this within their product literature.

Overview Background

Some propane regulator manufacturers have recently extended the service-life recommendation of some propane regulators. The propane industry deemed it important to determine if there was scientific or engineering evidence to support a greater than a 15-year replacement recommendation, as well as for the recently extended service life recommendation for some models.

GTI in its initial investigation of pertinent research found that the Gas Safety R&D Center of the Korea Gas Safety Corporation had conducted research on the aging characteristics of low-pressure LPG regulators in the 1990s. In evaluating how time affected performance characteristics and service life, researchers found deterioration in the material properties, most notably springs and diaphragms, after 5-6 years of service. Details regarding this testing are discussed in more detail under the section on Literature Search Results.

Based upon this information, research was warranted to investigate what service life the propane industry can expect from the regulators already in use.

Objective

The objective of this research was to provide an annotated review of available information worldwide on low-pressure propane regulators with focus on recommended service life and to the extent possible the basis for cited recommendations.

Approach

U.S. manufacturers market low-pressure propane/LPG regulators worldwide. These regulators are constructed to comply with U.S. standards and then separately certified for use in overseas markets. For this reason, the focus of this review was on U.S. manufacturers, specifically the three companies that occupy a majority of the regulator market share: Fisher, RegO®, and Sherwood.

GTI reviewed manufacturers’ literature from Fisher, RegO®, and Sherwood and concentrated on additional research conducted by the Korean Gas Safety Corporation. In addition, GTI reviewed relevant codes and standards, and reviewed the abstracts of peer-reviewed research on materials. GTI supplemented this review with follow-up discussion with materials and analytical personnel, and with the regulator manufacturers.

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Literature Search Results This section presents findings of GTI’s literature search. Areas of focus include elastomers, metals, propane composition, codes and standards, manufacturer’s literature, and missing data.

Elastomers

• A review of basic reference materials on elastomers included: “The Vanderbilt Rubber Handbook -13th Edition”, (Ohm, 1990), “Rosato’s Plastics Encyclopedia and Dictionary” (Rosato, 1993), and “Elastomeric Seals 101 – A Brief Tutorial”, (Grethlein, Craig, Lane 2004) is summarized below.

Elastomers, or elastic polymers, refer to rubber and synthetic materials that exhibit high elastic behavior and is often used interchangeably with the term rubber. Synthetic rubber materials, typically a nitrile, are used in the valve seat disc and diaphragm of propane regulators. Component specifications focus on dimensions and performance characteristics, not on elastomer composition. In some cases, “branded” elastomers are specified to assure an expected product purity and performance level.

Additives are used in elastomer formulations to overcome processing issues, performance limitations, to maintain product stability or to extend the batch and increase profitability. Two additives of interest to this investigation are plasticizers and extenders.

Plasticizers are additives used to keep polymers soft and pliable. Plasticizers are physically bound in the elastomer matrix but can leach out of the material over time. This effect is dependent upon the type and quantity of plasticizer being used and the operating environment. Loss of plasticizer can result in both physical and performance changes in the materials: an increase in hardness and brittleness, and a loss in elongation. With respect to LP-Gas regulators, the loss of plasticizer can affect the performance of valve seat discs and diaphragms.

Extenders are relatively inexpensive materials that can be added to more valuable elastomers to increase the amount of material in useful form without significantly lessening the compositions properties. Extenders are similar to plasticizers in that they are physically bound in the elastomer matrix and can migrate over time effecting elastomer performance. Some plasticizers are used as extenders.

• In a Korean Gas Safety Corporation Paper, “Aging Characteristics of Low Pressure LPG Regulators for Domestic Use”, (Kim, Kwon 1999) results showed that in general the safety devices of the low-pressure regulators deviated from normal operation after a year of service and deviated from the discharge start and reset pressures of the new regulators. Overall, the operating and closing pressures also deviated from the pressure range of the new regulators after a year of service. A 6 year service life was

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determined. The test sample included 160 low pressure LPG regulators in service from 1988 to 1997, and 6 new LPG regulators, for a total of 166 regulators tested.

Diaphragms from the LPG regulators were tested for tensile strength and elongation. Results showed a loss of tensile strength and decreased elongation after 5 years of service. Researchers suspect a hardening of the diaphragms due to leaching of plasticizers from rubber materials over time.

The paper called for further research to improve diaphragm durability and reliability, to investigate the effect of plasticizers extraction from rubber materials on diaphragm performance, and the development of new rubber materials with improved rubber characteristics and properties.

While the basic designs of the LPG regulators tested are similar to those manufactured in the U.S., none of the regulators tested were U.S. manufactured.

• “An Assessment of the Merit of Conditioning LP Gas Hoses Volume I & II”, (Battelle, 2005) documents and confirms research in France, Japan, and Canada that chemicals, mainly plasticizers, leach from hoses when in contact with LP Gas liquids.

• “Extraction Properties in LPG High Pressure Rubber Hoses”, (Kwon 2003) investigated the leaching of plasticizers in propane hoses. Findings indicate characteristic changes and failure in the butadiene rubber (NBR) used LPG high pressure regulators hoses.

• “The Effects of LPG Trace Contaminants on Rubber Properties”, (Kwon 2003) found a change in LPG regulator rubber materials when they were exposed to trace contaminants in LP-Gas composition.

• “Nitrile Rubber - Past, Present, and Future" (Hertz, Bussem, Ray 1994) cites the fact that nitrile rubber is an elasotomer that has been used in the oil and gas industry for 50 years, and that there have been occasional field failures due to elastomer hardening. The paper studied the effect of different solutions on the aging process of the nitrile. Although the research couldn't duplicate low temperature field failures, they found that iron was present for all of the field failures and acted as a catalyst.

While the research focused on extreme conditions found in gas supply and processing, it raises the question of propane quality which may be an area of further investigation.

• “Investigation of the Causes of Leaks in Natural Gas Pipeline Compression Couplings” (Environ 2005) determined that aging styrene butadiene rubber (SBR) and nitrile rubber (NBR) elastomer seals, a change in natural gas composition (lower concentration of pentane and heavier hydrocarbons (C5+) compounds), and low winter temperatures contributed to the failure of elastomer seals in pipeline compression couplings.

In the above investigation, dimensional changes in elastomer seals were due to the ability of the seals to adsorb and desorb pentane, hexane, and other higher hydrocarbons found in natural gas. Related to this investigation, the research

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demonstrates how variability in concentrations of C5+ compounds impacts elastomer performance.

Metals

Metals used in regulators are selected based upon their ability to perform under the conditions to which they are subjected. The literature search results of pertinent information include:

• UL 144 LP-Gas Regulators specifies cadmium and zinc plating to provide resistance to corrosion. In addition, UL 144 has specific metal requirements for regulator bodies and bonnets; nonmetallic materials cannot be used. Specified metals include aluminum alloys, ductile (nodular) iron, malleable iron, high-strength grey iron Class 40B, copper alloys, steel, and zinc alloys.

• In “Aging Characteristics of Low Pressure LPG Regulators for Domestic Use” (Kim, Kwon 1999), testing of LPG regulators springs that had been in the field found a loss in tensile strength after 7 years of service life. The authors called for spring research on the length of the freedom field of the spring, the surface treatment on the ending parts of the spring, quality control in the manufacturing, and reinforcement of durability characteristics.

• “Sulfide Stress Cracking and the Commercial Application of NACE MR0175-84” (Adams, Gossett 1984) discusses materials used to avoid sulfide stress cracking (SSC) in metals. While the standard is clearly intended to be used only for oil field equipment, industry has taken MR0175 and applied it to many other areas including refineries, LNG plants, pipelines and natural gas systems. The document is constructive and identifies ways to prevent SSC failures wherever H2S is present and includes a discussion of appropriate metals and requirements for regulator components.

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Propane Composition

LPG for domestic use meets commercial grade specifications as specified in both ASTM D1835 and GPA Standard 2140, listed in Table 1. Results from the previous discussion on elastomers, however, found variability in LPG composition and trace contaminants in LPG as possible contributors to changes in the performance of elastomers and their additives.

Table 1 GPA Liquefied Petroleum Gas Specifications Product Characteristics Commercial Grade Test Method Composition Predominately propane and /or

propylene. ASTM D-2163-91

Vapor Pressure at 100°F, psig, max. at 37.8°C,kPa(ga), max.

208 1434

ASTM D-1267-95

Volatile residue: Temperature at 95% evaporation, °F, max. Or °C, max. Butane and heavier, liquid volume percent max. Pentane and heavier, liquid volume percent max.

-37

-38.3 2.5

---

ASTM D-1837-94 ASTM D-2163-91 ASTM D-2163-91

Residual matter: Residue on evaporation of 100 ml, max. Oil stain observation

0.05 ml Pass (1)

ASTM D-2158-92 ASTM D-2158-92

Corrosion, copper strip, max. No.1 ASTM D-1838-91(Note A)

Total Sulfur, ppmw 185 ASTM D-2784-92

Moisture content pass GPA Propane Dryness Test

(Cobalt Bromide) or D-2713-91

Free water content --- --- (1) An acceptable product shall not yield a persistent oil ring when 0.3 ml of solvent residue mixture is added to a filter paper in 0.1 increments and examined in daylight after 2 minutes as described in ASTM D-2158. Note A: “This method may not accurately determine the corrosivity of the liquefied petroleum gas if the sample contains corrosion inhibitors or other chemicals which diminish the corrosivity of the sample to the copper strip. Therefore, the addition of such compounds for the sole purpose of biasing the test is prohibited.”

Source: Extracted from GPA Standard 2140-97

Research funded by the PERC on handheld devices for detecting LP-Gas contaminants identified typical types of LP-Gas contaminants found in LP-Gas samples, as found in Table 2. Many of these contaminants can negatively impact regulator performance.

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Table 2 Typical Trace Contaminants Found in LP-Gas

ammonia

methanol

water

excessive sulfur

fluorides

metal particles

common dirt

heavy hydrocarbons

plasticizers

excessive ethane, butane ethylene, propylene, etc

Source: Investigation of Portable or Handheld Devices for Detecting Contaminants”, (Hutzler, Johnson 2005)

• In “Investigation of Portable or Handheld Devices for Detecting Contaminants”, (Hutzler, Johnson 2005), found the following:

- A consensus belief exists among the propane industry that at the point of production or import most propane adheres to an HD-5 specification.

- LP-Gas contamination occurs at various points in the supply chain most probably in small quantities over an extended period of time.

- LP-Gas contaminants can include water, oily or waxy residues (from storage caverns, compressors, pipe dopes, gaskets, hoses, heat transfer fluids), ammonia (potentially serious for promoting copper and brass corrosion), and other corrosion agents that include fluorides, chlorides, bromides, hydrogen sulfide, and sulfur.

- The impact of these propane contaminants and off-specification gas is not well documented.

Research is warranted to investigate the effect of LP-Gas contaminants and off-specification gas on U.S. LPG regulator performance.

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Codes & Standards Review

LP-Gas is the primary fuel of choice for heating in 5 percent of all households in the United States. It is through the International Fuel Gas Code, the National Fuel Gas Code (NPFA 54), and the Liquid Petroleum Gas Code (NFPA 58), along with the referenced standard on LP-Gas Regulators (UL 144), ensures that LP-Gas is safe and useable for consumers.

A review of the codes and standards pertinent to LP-Gas regulator safety was important to determine to what extent useful or service life was addressed within their requirements.

UL 144 LP-Gas Regulators is the current performance standard for LP-Gas regulators. Codes and standards that reference UL 144 including NFPA 54: National Fuel Gas Code, NFPA 58: Liquid Petroleum Gas Code and ANSI Z21.18a-2001/CSA 6.3a Gas Appliance Pressure Regulators are silent on useful or service life of LPG system components. UL 144 LP-Gas Regulators

UL 144 LP-Gas Regulators is a safety standard whose requirements cover the construction, performance, manufacturing and production test, and markings of pressure regulators for use with LPG equipment. UL 144 is referenced by the following standards:

• Liquefied Petroleum Gas Code, (National Fire Codes, Vol. 2) NFPA 58; • National Fuel Gas Code (IAS/A.G.A. Z223.1), NFPA 54; • Outdoor Cooking Gas Appliances, IAS/A.G.A. Z21.58; and • Standard on Recreational Vehicles (RVIAA119.2) (National Fire Codes, Vol. 7),

NFPA 501C. The requirements include tests to verify outlet pressure stability characteristics within the manufacturer's rated capacity.

Standard Requirements

Temperature - Regulators covered by UL 144 must be capable of being used when exposed to ambient temperatures within the range of minus 40°F – plus 130°F (minus 40°C – plus 55°C).

Materials for a part are selected based upon its capability to perform under the conditions to which it is subjected. While test requirements are designed to ensure acceptable long-term performance, no determination of “useful” life is made and such a determination is outside the scope of this consensus standard.

• “A part of a regulator in contact with LP-Gas shall be resistant to the action of the fluid under the service conditions to which it is subjected.”

• Elastomeric materials are to be subjected to the following tests:

- LP-Gas Compatibility Test (Section 30);

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- ASTM D471 Test Method for Rubber Property- Effect of Liquids specifically volume test (Section 31) and weight loss test (Section 32);

- Accelerated-Aging Test (Section 33); - Low Temperature Test (Section 34).

• Polymeric materials are to be subjected to following tests: - LP-Gas Compatibility Test (Section 30), - Accelerated-Aging Test (Section 33).

• “When corrosion of a part interferes with the function of the regulator or corrosion results in deterioration, the part shall be of a corrosion-resistant material or be provided with a corrosion-resistant protective coating.”

- Cadmium and Zinc plating are specified to provide resistance to corrosion.

• The body and bonnet of a regulator must be made of a specified metal; nonmetallic material cannot be used. Specified metals include:

- Aluminum alloys, - Ductile (nodular) iron, - Malleable iron, - High-strength Grey Iron Class 40B - Copper alloys, - Steel, - Zinc alloys.

• The 10-Day Moist Ammonia-Air Stress Cracking (Section 29) on brass parts containing more than 15 percent zinc.

• Endurance Test to prove performance over specified number of cycles. Underwriters Laboratories’ UL 144 LP-Gas Regulators is the current performance standard for LP-Gas regulators and is designed for new regulators, not regulators that have been in the field. UL 144 is silent on the issue of service or useful life. Test requirements for materials in UL 144 are found in American Society of Testing and Materials (ASTM) standards that are designed to be an indicator of long-term performance.

NFPA 54: National Fuel Gas Code

NFPA 54: National Fuel Gas Code is an ANSI accredited consensus safety code for gas piping systems on consumers’ premises. NFPA 54 covers the installation of gas utilization equipment and accessories for use with fuel gases such as natural gas, manufactured gas, liquefied petroleum gas in the vapor phase, liquefied petroleum gas-air mixtures, or mixtures of these gases.

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NFPA 54 coverage of the gas piping systems includes the design, fabrication, installation, testing, operation, and maintenance of gas piping systems from the point of delivery to the connections with each gas utilization device.

The LP-Gas systems covered by this NFPA 54 are limited to a maximum operating pressure of 20 psig. The code requires that systems operating below -5°F must be designed to either accommodate liquid LP-Gas or prevent LP-Gas vapor from condensing back into liquid.

NFPA 54 coverage of gas utilization equipment includes the installation of gas utilization equipment, related accessories, and their ventilation and venting.

NFPA 54 is silent on useful or service life of LP-Gas system components and references UL 144 with regards to pressure relief valve discharge and over pressure shutoff of LP-Gas regulators.

NFPA 58: Liquefied Petroleum Gas Code

NFPA 58: Liquefied Petroleum Gas Code is an ANSI accredited consensus code that applies to the construction, installation, and operation of fixed and portable liquefied petroleum gas systems in bulk plants and commercial, industrial (with specified exceptions), institutional, and similar properties.

NFPA 58 coverage also includes truck transportation of liquefied petroleum gas; engine fuel systems on motor vehicles and other mobile equipment; storage of containers awaiting use or resale; installation on commercial vehicles; and liquefied petroleum gas service stations.

NFPA 58 is silent on useful or service life of LP-Gas system components and references UL 144 with regards to pressure relief valve discharge and over pressure shutoff of LP-Gas regulators.

ANSI Z21.18a-2001/CSA 6.3a Gas Appliance Pressure Regulators

ANSI Z21.18a-2001/CSA 6.3a Gas Appliance Pressure Regulators is a standard that details test and examination criteria for gas appliance pressure regulators for use with natural, manufactured, and mixed gases, liquefied petroleum gases and LP gas-air mixtures. Such devices, either individual or in combination with other controls, are intended to control selected outlet gas pressures to individual gas appliances.

ANSI Z21.18a-2001/CSA 6.3a is silent on useful or service life of LP-Gas system components and references UL 144 with regards to pressure relief valve discharge and over pressure shutoff of LP-Gas regulators.

The literature review found that codes and standards referencing UL 144 including NFPA 54: National Fuel Gas Code, NFPA 58: Liquid Petroleum Gas Code and ANSI Z21.18a-2001/CSA 6.3a Gas Appliance Pressure Regulators are silent on useful or service life of LPG system components.

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US Regulator Manufacturing Literature Review A review of manufacturers’ literature was important to determine if there was scientific or engineering support for a 15-year or greater replacement recommendation, and if an extended service life recommendation for some models was warranted.

A substantial percentage of low-pressure propane/LPG regulators used worldwide are made by U.S. manufacturers. These regulators are constructed to comply with U.S. standards and then separately certified for use in overseas markets. For this reason, GTI focused its review of manufacturer’s literature to U.S. manufacturers. Specifically, GTI focused on three companies that together have a predominant share of the U.S. LP-Gas regulator market: Fisher, RegO®, and Sherwood.

RegO® recommends regulator service life of 25 yrs for regulators (except single-stage) manufactured after 1995; all other regulators have a service life of 15 years. Fisher recommends regulator replacement at 20 years, or over 15 years of age for regulators that have experienced conditions (corrosion, underground systems, flooding, etc.) that would shorten their service life. In email correspondence, Sherwood reported a recommended 25 year service life on many regulator models. However, a review of their literature to date found recommended service life of 15 years.1

Typical materials used in LPG regulators that were identified the literature include zinc or die cast aluminum bodies, chromate coatings, synthetic rubbers such as nitrile, and stainless steel springs. Service life attributes, or manufacturers’ stated features that influence service life include corrosion resistance coatings and relief valve seat (Fisher); Stainless steel relief valve spring and retainer (Fisher); and painted, heavy-duty zinc (RegO®). All three manufacturer’s literature reference National Propane Gas Association (NPGA) documents in discussions related to installation, inspection, maintenance, and safety. NPGA no longer supports these documents and has released these documents to the public domain provided that the NPGA is not attributed to these documents. Discontinued documents that are referenced include:

• NPGA Installation and Service Guide Book #4003, • NPGA Propane Safety and Technical Support Manual Bulletin T403, • NPGA Safety Pamphlet 306 “LP-Gas Regulator and Valve Inspection and

Maintenance”, • NPGA LPG Safety Handbook #0001, and • NPGA Bulletin #133-80.

These documents can no longer be referenced as NPGA documents and effort should be made by the manufacturers to acknowledge and correct this within their product literature.

1 Email correspondence with Jim Rockwood, Sherwood Harsco Corporation on November 02, 2005.

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Fisher Regulators

Fisher Regulators, a division of Emerson Process Management, serves the pressure regulator needs of process industries and natural gas utilities worldwide. Fisher Regulators offer pressure and flow control solutions in two broad product categories industrial and natural gas.

Products

Table 3 Fisher LP-Gas Regulators

Outlet Pressure Range Service Recommended

Replacement Life

First Stage Regulators

3-hundred series 10 psig (Non-adjustable)

Up to 900,000 Btu/hr ( approx. 360 SCFH LP)

15 yrs

6-hundred series Adjustable (4-6 psig or 8-12 psig model dependent)

Up to 2.4 MM Btu/hr (approx. 960 SCFH LP)

20 yrs

Second-Stage Regulators

3-hundred series

Compact design

9-13" WC (factory set at 11" WC)

Up to 270,000 Btu/hr

15 yrs

6-hundred series

High capacity internal relief valve

9-13" WC (factory set at 11" WC) or 13-20" WC (factory set at 18"WC) model dependent

Up to 1.4 MM Btu/hr 20 yrs

Double Failure Protection

HSRL series

High strength cast iron body

High capacity internal relief valve

9-13" WC (factory set at 11" WC)

Up to 2.1 MM Btu/hr

Integral Two-Stage Regulators

3-hundred series

Compact design

9-13" WC (factory set at 11" WC)

Up to 275,000 Btu/hr

15 yrs

6-hundred series 9(or 9.5 depending Up to 750,000 Btu/hr 20 yrs

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Outlet Pressure Range Service Recommended

Replacement Life

High capacity internal relief valve

on model)-13" WC (factory set at 11" WC)

Double Failure Protection

Materials2

“The R600 series use aluminum die cast casings which are chromate coated prior to painting. Fisher paints the parts prior to assembly. Relief valve springs are stainless steel. Main springs are carbon steel plated. Rubber materials are typically a nitrile or other special blend of synthetic rubber. Engineered designs are used for the pusher post/relief valve seat, adjusting screw and vent flapper parts. These are typically glass filled for added strength and moisture stability.”

“R300 series are built much the same except that the lower casing is zinc so that the flange areas can be crimped.”

“The new compact regulator uses much of the same material technology and as the R600 series. The coating and painting process is the same as the R600 series.”

Installation Considerations

The installation considerations shown below are from the Fisher regulator manuals. The manuals provide general safety precautions and can be categorized in terms of: 1) initial considerations, 2) proper venting, and 3) preventing in-service damage.

Initial Considerations

• Before installing the regulator, check for damage that might have occurred in shipment. Also check for and remove any dirt or foreign material that may have accumulated in the regulator body or the pipeline.

• Apply pipe compound to the male threads of the pipe -- caution has to be exercised as to not introduce pipe compound (foreign matter) in the regulator body.

• Make sure gas flow through the regulator is in the same direction as the arrow on the body “Inlet” and “Outlet” connections that are clearly marked.

2 Email correspondence with Jim Griffin May 25th 2005.

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15

Venting

• LP-gas may discharge to the atmosphere through the vent. An obstructed vent which limits air or gas flow can cause abnormally high pressure. Failure to use a vent line on indoor installations can cause a hazardous accumulation of gas.

• Install the regulator so that any gas discharge through the vent or vent assembly is over 3-feet horizontally from any building opening below the level of discharge.

• Horizontally mounted regulators, such as those found in single cylinder installations, must be installed beneath a protective cover. If possible, slope or turn the vent down sufficiently to allow any condensation to drain out of the spring case.

• By code, regulators installed indoors have limited inlet pressure, and they require a vent line to the outside of the building.

Preventing In-Service Damage

• Protect the vent against the entrance of rain, snow, ice formation, paint, mud, insects, or any other foreign material that could plug the vent or vent line. According to a discussion with Jim Griffin of Fisher, the most predominant cause of pre-mature regulator failure is due to debris deposit inside the regulator.

• A regulator installed outdoors without a protective hood must have its vent pointed vertically down to allow condensate to drain. This minimizes the possibility of freezing and of water or other foreign material entering the vent and interfering with proper operation.

Maintenance Considerations

Due to normal wear or damage that may occur from external sources, these regulators must be inspected and maintained periodically. The frequency of inspection and replacement of the regulators depends upon the severity of service conditions or the requirements of local, state, and federal regulations. Visually inspect the regulator each time a gas delivery is made for:

• Improper installation.

• Plugged or frozen vent.

• Wrong regulator or no regulator in the system.

• Internal or external corrosion.

• Age of the regulator.

• Any other condition that could cause the uncontrolled escape of gas.

Warranty

5 year limited warranty.

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ce L

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16

Fis

her L

itera

ture

Res

ults

Tabl

e 4

Fish

er P

ropa

ne R

egul

ator

Ser

vice

/Saf

ety

Bulle

tins

Fish

er

Ref

eren

ce

Num

ber

Title

C

omm

ents

LP-7

P

rodu

ct S

peci

fic L

itera

ture

R-6

22H

Se

rvic

e Li

fe: 2

0 ye

ar R

ecom

men

ded

repl

acem

ent l

ife

-

It is

reco

mm

ende

d to

repl

ace

regu

lato

rs th

at a

re o

ver 1

5 ye

ars

of a

ge o

r tha

t hav

e ex

perie

nced

con

ditio

ns (c

orro

sion

, un

derg

roun

d sy

stem

s, fl

oodi

ng, e

tc.)

that

wou

ld s

horte

n th

eir

serv

ice

life.

(pag

e 39

)

Life

Attr

ibut

ion

-

Cor

rosi

on re

sist

ance

coa

tings

and

relie

f val

ve s

eat

-

Sta

inle

ss s

teel

relie

f val

ve s

prin

g an

d re

tain

er

R

efer

ence

s -

N

FPA

54,

“Nat

iona

l Fue

l Gas

Cod

e

Pip

e an

d tu

bing

siz

ing

(pag

e 18

, 23-

28)

-

NFP

A 5

8, “L

iqui

d P

etro

leum

Gas

Cod

e ”

C

onta

iner

loca

tion

and

inst

alla

tion

(pag

e 11

)

LP-1

0 LP

-Gas

Ser

vice

man

’s H

andb

ook

S

ervi

ce L

ife:

-

It is

reco

mm

ende

d to

repl

ace

regu

lato

rs th

at a

re o

ver 1

5 ye

ars

of a

ge o

r tha

t hav

e ex

perie

nced

con

ditio

ns (c

orro

sion

, un

derg

roun

d sy

stem

s, fl

oodi

ng, e

tc.)

that

wou

ld s

horte

n th

eir

serv

ice

life.

(pag

e 39

)

Ref

eren

ces:

-

N

FPA

54,

“Nat

iona

l Fue

l Gas

Cod

e

Pip

e an

d tu

bing

siz

ing

(pag

e 18

, 23-

28)

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ulat

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ervi

ce L

ife

17

-

NFP

A 5

8, “L

iqui

d P

etro

leum

Gas

Cod

e ”

C

onta

iner

loca

tion

and

inst

alla

tion

(pag

e 11

)

Pip

e an

d tu

bing

siz

ing

(pag

e 18

)

Reg

ulat

or In

stal

latio

n (p

age

34)

-

Fish

er B

ulle

tins

LP-1

8 an

d LP

-24

R

egul

ator

Fre

ezeu

ps (p

age

32)

-

UL

144

and

Fish

er B

ulle

tin L

P-1

5

Reg

ulat

or In

stal

latio

n, o

pera

tion

and

mai

nten

ance

(pag

e 33

) -

Fi

sher

Bul

letin

LP

-32

R

egul

ator

Insp

ectio

n (p

age

39)

-

NP

GA

Saf

ety

Bul

letin

306

[Dis

cont

inue

d]

Tr

oubl

esho

otin

g do

mes

tic ta

nk fi

tting

s (p

age

40)

LP-1

2 R

egul

ator

Sel

ectio

n A

nd P

ipe

Siz

ing

Cha

rt

Han

dy re

fere

nce

guid

e fo

r sel

ectin

g Fi

sher

regu

lato

rs w

ith

conv

enie

nt m

etho

d of

siz

ing

pipe

on

the

reve

rse

side

.

LP-1

5 G

ive

A R

egul

ator

the

Atte

ntio

n it

Des

erve

s

Exp

lain

s ho

w d

omes

tic s

elf-o

pera

ted

regu

lato

rs w

ork;

giv

es

inst

alla

tion

and

mai

nten

ance

tips

. -

Is

sues

Free

ze U

p pr

even

tion

C

hips

Vap

or fa

ll ou

t

Ser

vice

Life

: Not

add

ress

ed

R

efer

ence

s:

-

NFP

A 5

4, “N

atio

nal F

uel G

as C

ode

P

RV

dis

cuss

ion

(p1)

Inst

alla

tions

as

per (

p2)

-

NFP

A 5

8, “L

iqui

d P

etro

leum

Gas

Cod

e ”

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ervi

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18

PR

V d

iscu

ssio

n (p

1)

In

stal

latio

ns a

s pe

r (p2

)

LP-1

8 H

ow D

rip-L

ips

Can

Pre

vent

R

egul

ator

Fre

eze-

Ups

Sho

ws

how

drip

lip

styl

e ve

nts

can

redu

ce th

e po

ssib

ility

of v

ent

bloc

kage

due

to fr

eezi

ng ra

in.

LP-1

9 H

ow to

Kee

p Y

our I

nter

nal V

alve

s W

orki

ng

A d

iscu

ssio

n ab

out t

he o

pera

tion,

inst

alla

tion

and

mai

nten

ance

of F

ishe

r’s C

-S

erie

s In

tern

al V

alve

s.

LP-2

4 P

lain

Fac

ts a

bout

free

zing

R

egul

ator

s D

escr

ibes

how

a re

gula

tor c

an fr

eeze

inte

rnal

ly a

nd g

ives

tips

to p

reve

nt th

is

situ

atio

n.

LP-2

9 C

ompl

ying

with

NFP

A 5

8 Tr

ansf

er

Are

a R

ulin

gs

An

over

view

of t

he N

FPA

requ

irem

ents

with

exa

mpl

es o

f acc

epta

ble

equi

pmen

t

LP-3

1 In

spec

ting

LP-G

as R

egul

ator

s.

Wha

t to

Look

For

D

iscu

sses

ser

vice

life

, red

ucin

g ve

nt b

lock

age,

cor

rosi

on, i

nspe

ctio

n, e

tc.

LP-3

2 In

spec

ting

LP-G

as R

egul

ator

s.

Wha

t to

Look

For

D

iscu

sses

ser

vice

life

, red

ucin

g ve

nt b

lock

age,

cor

rosi

on, i

nspe

ctio

n, e

tc.

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RegO® Regulators

RegO® Valves and Regulators are sold by a network of distributors and agents throughout the United States, Canada, and over 100 countries around the globe.

Products

Table 5 RegO® LP-Gas Regulators

Outlet Pressure Range Service Recommended

Replacement Life

First Stage Regulators

LV3303TR series

Compact design

10 psig (Non-adjustable)

Up to 1.5 MM Btu/hr 25 yrs

(Post 1995 Only)

LV4403SR/TR series

Built-in pressure gauge

Adjustable (1-5 or factory set at either 5-10 psig - model dependent)

Up to 2.5 MM Btu/hr 25 yrs

(Post 1995 Only)

Second-Stage Regulators

LV4-thousand series

Incorporate integral relief valve

9-13" WC (or 2 psig@10 psig inlet depending on model).

Up to 1 MM Btu/hr

25 yrs

(Post 1995 Only)

LV5-thousand series

Incorporate integral relief valve

9-13" WC (factory set at 11" WC) or 13-20" WC (factory set at 18"WC) - model dependent

Up to 2.2 MM Btu/hr 25 yrs

(Post 1995 Only)

Twin Stage Regulators

LV404B4/LV404B9 Series

Relief vent on the first stage is consistently in the down position

9-13" WC (factory set at 11" WC)

Up to 525,000 Btu/hr

25 yrs

(Post 1995 Only)

LV404B23/LV404B29 Series

May be used with a variety of pigtails, inlet adapters and manifolds

9-13" WC (factory set at 11" WC)

Up to 200,000 Btu/hr 25 yrs

(Post 1995 Only)

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Materials

Tables 6 and 7 below summarize the construction materials that RegO® uses for its low-pressure propane/LP-Gas regulators.

Table 6 Component Materials by RegO® Regulator Series LV3303TR

Series LV4403SR

and TR Series

LV4403B Series

LV4403B66RA Series

LV4403Y Series

Body Zinc Die Cast Zinc

Die Cast Zinc Die Cast Aluminum

Die Cast Zinc

Bonnet Zinc Die Cast Zinc

Die Cast Zinc Die Cast Zinc Die Cast Zinc

Nozzle Orifice Brass Brass Brass Brass

Spring Steel Steel Steel Steel Steel

Valve Seat Disc Resilient Rubber

Resilient Rubber

Resilient Rubber

Resilient Rubber

Resilient Rubber

Diaphragm Integrated Fabric and Synthetic Rubber

Integrated Fabric and Synthetic Rubber

Integrated Fabric and Synthetic Rubber

Integrated Fabric and Synthetic Rubber

Integrated Fabric and Synthetic Rubber

Table 7 Component Materials by RegO® Regulator Series LV5503Y

Series LV5503B Series

LV404B4 and LV404B9 Series

LV404B23 Series

LV404B29 Series

Body Die Cast Aluminum

Die Cast Aluminum

1st Stage – Brass 2nd Stage – Die Cast Zinc

1st Stage – Die Cast Zinc 2nd Stage – Die Cast Zinc

1st Stage – Die Cast Zinc 2nd Stage – Die Cast Zinc

Bonnet Die Cast Aluminum

Die Cast Aluminum

Die Cast Zinc 1st Stage – Die Cast Zinc 2nd Stage – Die Cast Zinc

1st Stage - Brass 2nd Stage – Die Cast Zinc

Nozzle Orifice Brass Brass

Spring Steel Steel Steel Steel Steel

Valve Seat Disc Resilient Rubber

Resilient Rubber

Resilient Rubber

Resilient Rubber

Diaphragm Integrated Fabric and Synthetic Rubber

Integrated Fabric and Synthetic Rubber

Integrated Fabric and Synthetic Rubber

Integrated Fabric and Synthetic Rubber

Integrated Fabric and Synthetic Rubber

Installation Considerations

The installation considerations shown below are from the RegO® regulator manuals. The manuals provide general safety precautions and can be categorized in terms of: 1) proper venting 2) conformance to code, and 3) leak testing.

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General Safety Precautions

Regulators should be installed with the vent facing down or protected so their operation will not be affected by the elements.

The vents and/or discharge tubes must be protected from the elements and must be equipped with a screen to prevent bugs from obstructing the opening.

It should not be necessary to remind readers that regulators must be installed in strict conformance with NFPA Pamphlets 54 and 58, and all other applicable codes and regulations.

Always test for leaks at time of installation and inspect for leaks if there is reason to believe that pipe connections could cause a hazard.

Maintenance Requirements

Regulator inspection for corrosion should be made according to the guidelines listed below:

For underground installations subject to submersion, the regulator should be inspected every time the container is filled.

For known corrosive atmospheres of salt air or chemical pollution, the regulator should be inspected at least once a year.

For other applications, the regulator should be inspected every 3 years.

A casual inspection for corrosion can be made by examining the surface and looking into the bonnet after the bonnet cap has been removed. This sometimes will alert the inspector to corrosive conditions.

If any corrosion is evident, replace the regulator.

Warranty

LIMITED WARRANTY

Engineered Controls International, Inc warrants its regulators and repair kits that it manufactures and sells to be free from manufacturing defects only for a period of 12 months from installation or 18 months from the factory shipping date, whichever is earlier. Engineered Controls International, Inc will repair, replace or refund defective material if notified by the buyer within 30 days of discovery but not without obtaining written consent.

Defective items due to misuse, alteration or neglect are not covered in the warranty. Engineered Controls International, Inc is not to be held liable for any loss, cost of repair, or damages of any kind connected with the use, sale or repair of any of their products. This warranty applies only to products installed and used according to Engineered Controls International, Inc.’s printed instructions.

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ervi

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22

Reg

O® L

itera

ture

Res

ults

Tabl

e 8

RegO

® P

ropa

ne R

egul

ator

Ser

vice

/Saf

ety

Lite

ratu

re S

earc

h Re

sults

Item

Ti

tle

Com

men

t on

Serv

ice

Life

L-54

5 LP

-Gas

Ser

vice

man

’s M

anua

l

Ref

eren

ces:

-

N

FPA

54,

"Nat

iona

l Fue

l G

as C

ode"

Pip

e S

izin

g Ta

ble

(p20

-22)

,

Indo

or re

gula

tor r

estri

ctio

n (p

30)

S

ectio

n on

Insp

ectio

n, T

estin

g an

d P

urgi

ng (p

34),

Le

ak te

st (p

37),

-

NFP

A 5

8, "L

ique

fied

Pet

role

um G

as C

ode"

Cyl

inde

r pla

cem

ent (

p12-

14)

P

ipe

Siz

ing

Tabl

e (p

20)-

22,

S

ingl

e S

tage

Reg

ulat

or re

stric

tions

(p26

),

Ven

ting

(p29

),

Indo

or re

gula

tor r

estri

ctio

n (p

30)

-

NP

GA

Pro

pane

Saf

ety

and

Tech

nica

l Sup

port

Man

ual

Bul

letin

T40

3 –

Pur

ging

(p37

), [D

isco

ntin

ued]

-

R

egO

® P

rodu

cts

Safe

ty W

arni

ng W

B-3

Exc

ess

flow

val

ves

(p38

) -

R

egO

® Pr

oduc

ts S

afet

y W

arni

ng W

B-6

Pre

ssur

e R

elie

f V

alve

(p40

)

L-50

0 LP

-Gas

& A

nhyd

rous

Am

mon

ia E

quip

men

t

Serv

ice

Life

-

W

hen

all o

f the

se re

com

men

datio

ns a

re fo

llow

ed, t

he

reco

mm

ende

d se

rvic

e lif

e of

an

EC

II/R

egO

® re

gula

tor

(exc

ept s

ingl

e st

age)

man

ufac

ture

d af

ter 1

995

is 2

5 ye

ars

(A5)

.

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Item

Ti

tle

Com

men

t on

Serv

ice

Life

-

The

reco

mm

ende

d se

rvic

e lif

e of

all

othe

r EC

II/R

egO

®

regu

lato

rs is

15

year

s (A

5).

W

arni

ng:

-

All

EC

II® p

rodu

cts

are

mec

hani

cal d

evic

es th

at w

ill

even

tual

ly b

ecom

e in

oper

ativ

e du

e to

wea

r, co

rros

ion

and

agin

g of

com

pone

nts

mad

e of

mat

eria

ls s

uch

as ru

bber

. Th

e en

viro

nmen

t and

con

ditio

ns o

f use

will

dete

rmin

e th

e sa

fe s

ervi

ce li

fe o

f the

se p

rodu

cts.

Insp

ectio

n an

d m

aint

enan

ce o

n a

perio

dic

basi

s is

ess

entia

l (A

3).

-

Life

of a

regu

lato

r is

dete

rmin

ed b

y th

e en

viro

nmen

t in

whi

ch it

“liv

es.”

(A2,

A7)

Rec

omm

enda

tions

-

N

otic

e P

erio

dic

Inst

alla

tion

and

mai

nten

ance

sho

uld

be

perfo

rmed

onl

y by

qua

lifie

d pe

rson

nel (

A3).

-

Filte

r The

use

of a

n in

-line

filte

r sho

uld

be c

onsi

dere

d w

hen

othe

r sys

tem

com

pone

nts

may

be

uncl

ean

and

the

syst

em

cont

amin

ated

by

rust

, sca

le, d

irt, d

ebris

or o

ther

fore

ign

mat

eria

l (A3

).

Cau

ses

of F

ailu

re

-

Hig

h P

ress

ure

(A5-

6),

-

Leak

s (A

6),

-

Loss

of P

ress

ure

(A7)

.

Res

pons

ibili

ty S

tate

men

t (A

7) N

OTE

: The

re is

a d

evel

opin

g tre

nd in

sta

te le

gisl

atio

n an

d in

pro

pose

d na

tiona

l leg

isla

tion

to

mak

e th

e ow

ners

of p

rodu

cts

resp

onsi

ble

for r

epla

cing

pro

duct

s be

fore

they

reac

h th

e en

d of

thei

r saf

e us

eful

life

. LP

-Gas

de

aler

s sh

ould

be

awar

e of

legi

slat

ion

whi

ch c

ould

affe

ct th

em.

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ulat

or S

ervi

ce L

ife

24

Item

Ti

tle

Com

men

t on

Serv

ice

Life

R

efer

ence

s:

-

NP

GA

Saf

ety

Pam

phle

t 306

“LP

-Gas

Reg

ulat

or a

nd V

alve

In

spec

tion

and

Mai

nten

ance

.” (A

5), [

Dis

cont

inue

d]

-

NFP

A 5

4, "N

atio

nal F

uel

Gas

Cod

e" (A

5),

-

NFP

A 5

8, "L

ique

fied

Pet

role

um G

as C

ode"

(A5)

,

Life

Attr

ibut

ion

(A13

) Pai

nted

, hea

vy-d

uty

zinc

(bod

y an

d bo

nnet

) res

ists

cor

rosi

on a

nd g

ives

long

-life

pro

tect

ion,

eve

n un

der “

salty

air”

con

ditio

ns. (

LV44

03)

L-

Reg

O® D

eter

min

atio

n G

uide

Gui

de fo

r det

erm

inin

g ag

e an

d ty

pe o

f reg

ulat

ors;

iden

tific

atio

n of

regu

lato

rs “b

eyon

d th

eir s

afe

serv

ice

life”

.

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25

Sherwood Regulators

Sherwood, a division of Harsco, is an ISO 9001 certified manufacturer of LP-Gas regulators and other propane and natural gas equipment. In 1996, Sherwood merged with the Taylor-Wharton Gas Equipment division of Harsco. Sherwood LP gas regulators occupy the third place in the market place trailing Fisher and Rego®; however Sherwood has a more diversified line of regulators for the compressed gas industry including industrial, chlorine, medical, welding, specialty, semiconductor, life support and LP-Gas.

Products

Table 9 Sherwood LP-Gas Regulators

Outlet Pressure Range

Service Recommended Replacement Life

First Stage Regulators

Adjustable (5-15 psig (Factory set at 10 psig)

Up to 1.1 MM Btu/hr 15 yrs

Second-Stage Regulators

straight-through design

right angle design

9-13" WC (Factory set at 11" WC)

Up to 800,000 Btu/hr 15 yrs

Integral Two-Stage Regulators

920 Series

Bonnet vent position above outlet or 90° to outlet design

9-13" WC or 13-18" depending on model (Factory set at 11" WC or 15" WC depending on model)

Up to 550,000 Btu/hr

15 yrs

921 Series

Bonnet vent position above outlet or 90° to outlet

9-13" WC or 13-18" depending on model (Factory set at 11" WC or 15" WC depending on model)

Up to 550,000 Btu/hr 15 yrs

Materials

Regulator features include Heavy zinc die casting to eliminate porosity. Materials used in Sherwood LP gas regulators could not be determined through available literature.

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Literature Review of Regulator Service Life

26

Installation Considerations

The installation considerations given in the Sherwood regulator manuals are general safety precautions.

Safety Precautions

Make sure the lines to the regulator are free of all foreign matter. Blow out all the lines prior to installing the regulator. If foreign matter should become embedded in the regulator seat, it could cause high lockup pressure. The rising pressure could activate the pressure relief device inside the regulator.

Consider using in-line filters to help prevent contaminates from entering the regulator.

To protect the regulator from ice, snow and sleet, mount the regulator under a hood or covering. Make sure the vent is pointing downward. This allows moisture collected above the diaphragm to drain out through the vent.

Undersized piping reduces delivery pressure because of increased friction. The regulator must never be adjusted for higher outlet pressures to compensate for undersized lines. This could result in high lockups, fluctuating pressures, and inefficient combustion.

Maintenance Requirements

In email correspondence, Sherwood reported a recommended 25 year service life on many regulator models. However, a review of their literature to date found recommended service life of 15 years.3

Sherwood regulators must be routinely inspected according to industry standards, and replaced after a maximum of fifteen (15) years of use. Regulators that are exposed to extreme heat, cold or other severe environmental conditions must be inspected and replaced more often. Check the regulator frequently to make sure the vent is not plugged by mud, ice, insects or any other foreign matter. Vents must be clear and fully open at all times to ensure proper operation.

Warranty

Sherwood warrants its regulators that it manufactures and sells to be free from manufacturing defects only for a period of three years from date of shipment. Sherwood will repair or replace defective material at its factory but not without obtaining written consent. Defective items due to misuse, alteration or neglect are not covered in the warranty; nor are Sherwood to be held liable for any loss, cost of repair, or damages of any kind connected with the use, sale or repair of any of our products. This warranty applies when products are installed and used in accordance with NFPA and ANSI 3 Email correspondence with Jim Rockwood, Sherwood Harsco Corporation on November 02, 2005.

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Literature Review of Regulator Service Life

27

acceptable standards. No claims are made as to the ability of a particular product to be used in conjunction with products of other manufacturers.

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Lite

ratu

re R

evie

w o

f Reg

ulat

or S

ervi

ce L

ife

28

Sher

woo

d Li

tera

ture

Res

ults

Tabl

e 10

She

rwoo

d Pr

opan

e Re

gula

tor S

ervi

ce/S

afet

y Bu

lletin

s

Sher

woo

d R

efer

ence

N

umbe

r Ti

tle

Com

men

ts

LPG

-003

-99

She

rwoo

d LP

G P

rodu

cts

R

egul

ator

s (L

PG P

rodu

cts

Sect

ion)

-

Mee

t UL

Sta

ndar

d 14

4 an

d N

FPA

Pam

phle

t #58

. (p

3.1)

-

War

rant

y: A

ll S

herw

ood

regu

lato

rs a

re c

over

ed b

y a

thre

e-ye

ar li

mite

d re

plac

emen

t war

rant

y (p

3.1

)

Se

rvic

e Li

fe (p

1) :

-

Rec

omm

ends

repl

acem

ent a

fter (

15) y

ears

of u

se.

-

Sev

ere

envi

ronm

enta

l con

ditio

ns w

arra

nt in

spec

tion

and

repl

acem

ent m

ore

ofte

n.

-

Con

sult

the

Nat

iona

l Pro

pane

Gas

Ass

ocia

tion

(NP

GA

) for

in

spec

tion

and

repl

acem

ent i

nfor

mat

ion

O

ther

Ref

eren

ces

-

NFP

A 5

4, "N

atio

nal F

uel

Gas

Cod

e"

Q

ualif

ied

indi

vidu

als

mus

t hav

e a

wor

king

kno

wle

dge

of…

(p2.

1)

-

NFP

A 5

8, "L

ique

fied

Pet

role

um G

as C

ode"

Free

ze-u

p pr

even

tion

(p3)

As

per 1

995

editi

on …

two

stag

e re

gula

tors

are

now

m

anda

tory

in th

e U

nite

d S

tate

s. (p

2)

P

ipin

g ch

arts

(p2.

1)

Q

ualif

ied

indi

vidu

als

mus

t hav

e a

wor

king

kno

wle

dge

of…

(p2.

1)

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Lite

ratu

re R

evie

w o

f Reg

ulat

or S

ervi

ce L

ife

29

-

NP

GA

LP

G S

afet

y H

andb

ook

#000

1, [D

isco

ntin

ued]

Free

ze-u

p pr

even

tion

- Pro

duct

s S

ectio

n (p

3)

-

NP

GA

Bul

letin

#13

3-80

[Dis

cont

inue

d]

Fr

eeze

-up

prev

entio

n - P

rodu

cts

Sec

tion

(p3)

In

stru

ctio

n Sh

eets

Sec

tion

-

Not

ice:

All

She

rwoo

d pr

oduc

ts m

ust b

e us

ed in

stri

ct

com

plia

nce

with

NFP

A 5

4, "N

atio

nal F

uel

Gas

Cod

e"

N

FPA

58,

"Liq

uefie

d P

etro

leum

Gas

Cod

e"

-

Add

ition

al R

efer

ence

:

NP

GA

Inst

alla

tion

and

Ser

vice

Gui

de B

ook

#400

3.

[Dis

cont

inue

d]

Pr

essu

re R

elie

f Val

ves

(PR

Vs)

-

She

rwoo

d re

com

men

ds P

RV

s be

repl

aced

afte

r ten

(10)

ye

ars

of u

se.

-

Mai

nten

ance

pro

cedu

res

Ref

eren

ce

C

GA

Pam

phle

t S-1

.1, P

ress

ure

Rel

ief D

evic

e S

tand

ards

-Cyl

inde

rs, S

ectio

n 9.

1.

N

PG

A P

amph

let #

306,

LPG

Reg

ulat

or a

nd V

alve

In

spec

tion

and

Mai

nten

ance

[Dis

cont

inue

d]

N

FPA

Pam

phle

t #58

, Sto

rage

and

Han

dlin

g of

Li

quef

ied

Pet

role

um G

ases

.

NFP

A P

amph

let #

59, L

P G

ases

at U

tility

Gas

Pla

nts

Sa

fety

Gui

delin

es R

efer

ence

s.

-

NFP

A 5

4, "N

atio

nal F

uel

Gas

Cod

e"

-

NFP

A 5

8, "L

ique

fied

Pet

role

um G

as C

ode"

-

N

atio

nal P

ropa

ne G

as A

ssoc

iatio

n

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Lite

ratu

re R

evie

w o

f Reg

ulat

or S

ervi

ce L

ife

30

Te

chni

cian

s G

uide

Sec

tion

Ref

eren

ces

-

NFP

A 5

4, "N

atio

nal F

uel

Gas

Cod

e"

G

ener

al S

afet

y (p

1)

-

NFP

A 5

8, "L

ique

fied

Pet

role

um G

as C

ode"

Gen

eral

Saf

ety

(p1)

-

N

PG

A L

PG

Saf

ety

Han

dboo

k #0

001,

[Dis

cont

inue

d]

G

ener

al S

afet

y (p

1)

LPO

3B98

S

herw

ood

Tech

nici

an’s

Gui

de

to L

PG

Se

rvic

e Li

fe (p

45) :

-

R

ecom

men

ds re

plac

emen

t afte

r (15

) yea

rs o

f use

.

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Literature Review of Regulator Service Life

31

Conclusions The literature review was not able to document scientific or engineering support for a service-life recommendation of 15-years or greater. The findings of the literature review warrant further research in the use and variability of plasticizers and extenders in the rubber composition of LPG regulator components; the long-term effect a propane operating environment has on elastomer and spring performance; and the effect of LP-Gas contaminants and off-specification gas on U.S. LPG regulator performance.

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32

References 1. American Gas Association and National Fire Protection Association, National

Fuel Gas Code, NFPA 54/ANSI Z223.1, September, 2002.

2. Battelle, “An Assessment of the Merit of Conditioning LP Gas Hoses Volume I & II”, 2005.

3. C. Grethlein, B. D. Craig, R. A. Lane, “ELASTOMERIC SEALS 101 – A BRIEF TUTORIAL”, The AMPTIAC Quarterly, Volume 8, Number 2, pp11-19.

4. D. L. Hertz, Jr., H. Bussem, and T. W. Ray, "Nitrile Rubber - Past, Present & Future" Presented at a meeting of the Rubber Division, American Chemical Society Pittsburgh, Pennsylvania, October 11-14, 1994.

5. ENVIRON International Corporation, “Investigation of the Causes of Leaks in Natural Gas Pipeline Compression Couplings”, July 2005.

6. Fisher Product Literature, LP-7: Product Specific Literature; LP-10: LP-Gas Serviceman’s Handbook; LP-12: Regulator Selection And Pipe Sizing Chart Give A Regulator the Attention it Deserves; LP-15: How Drip-Lips Can Prevent Regulator Freeze-Ups; LP-18: How to Keep Your Internal Valves Working; LP-19: Plain Facts about freezing Regulators; LP-24: Complying with NFPA 58; LP-29: Transfer Area Rulings; LP-31: Inspecting LP-Gas Regulators. What to Look For; LP-32: Inspecting LP-Gas Regulators. What to Look For.

7. Gas Processors Suppliers Association, Engineering Data Book, Vol I, Sec 2 Product Specification, 2004.

8. Hutzler, Johnson, “Investigation of Portable or Handheld Devices for Detecting Contaminants”, 2005,

9. Jeong-Rock Kwon, Young-Gyu Kim Gas Safety R&D Center, Korea Gas Safety Corporation, “Aging Characteristics of Low Pressure LPG Regulators for Domestic Use”, May 1999.

10. Jeong-Rock Kwon, pGas Safety R&D Center, Korea Gas Safety Corporation, “Extraction Properties in LPG High Pressure Rubber Hoses”, 2003.

11. Jeong-Rock Kwon, Gas Safety R&D Center, Korea Gas Safety Corporation, “The Effects of LPG Trace on Rubber Properties”, May 1999.

12. Mark Adams, James L. Gossett, “Sulfide Stress Cracking and the Commercial Application of NACE MR0175-84” 1974, Updated 1984.

13. National Fire Protection Association, Liquid Petroleum Gas Code, NFPA 58, January, 2004.

14. National Fire Protection Association, Code Development Process, www.nfpa.org.

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33

15. National Propane Gas Association, “Copyright Waiver on Old Bulletins”, email correspondence with Bruce Swiecicki on May 4, 2005.

16. Ohm, Robert F., “The Vanderbilt Rubber Handbook -13th Edition”, R.T. Vanderbilt Company, Inc., 1990.

17. RegO® Product Literature, L-545: LP-Gas Serviceman’s Manual; L-500: LP-Gas & Anhydrous Ammonia Equipment; and RegO® Determination Guide.

18. Rosato, Dominick V., “Rosato’s Plastics Encyclopedia and Dictionary”, Oxford University Press, 1993.

19. Sherwood Product Literature, LPG-003-99: Sherwood LPG Products; LPO3B98: Sherwood Technician’s Guide to LPG.

20. Underwriters Laboratories Inc, LP-Gas Regulators, UL 144-1999, and revisions up to January, 2002.

21. Underwriters Laboratories Inc., “Method of Development and Maintenance of UL Standards for Safety”, 2004.

22. Gas Technology Institute, GRI-01/0169 “Gas Model Energy Code Support”, August 2001.

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Page 159: Performance, Durability, and Service Life of Low Pressure ... · Performance, Durability, and Service Life of vii September 2006 Low Pressure Propane Vapor Regulators Battelle Of

APPENDIX B

Comments Received on the Test Protocol and Battelle’s Response

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Page 161: Performance, Durability, and Service Life of Low Pressure ... · Performance, Durability, and Service Life of vii September 2006 Low Pressure Propane Vapor Regulators Battelle Of

Co

mm

en

ts o

n r

eg

ula

tor

test

pro

toco

l an

d a

sso

ciate

d j

ust

ific

ati

on

fo

r th

e r

evis

ed

pro

toco

l

Page

B-1

D

ate

C

om

men

t Fo

rmat

Co

mm

en

ter

Co

mm

en

t R

ela

ted

to

Co

mm

en

t R

esp

on

se (

Lead

ing

to

th

e f

inal te

st

pro

toco

l –

Att

ach

men

t 3

) Com

men

ts b

ase

d o

n r

egula

tor

test

pro

toco

l in

tern

ally

dis

trib

ute

d o

n 1

1/4

/2004 (

Att

achm

ent

1)

11/1

2/2

004

email

Dav

id

Kal

ensk

y Typ

e I

Rel

ief

Cap

acity

Tes

t •

Per

form

an a

dditio

nal re

lief

flow

at

3 p

sig.

• In

itia

l th

oughts

wer

e to

just

tes

t at

the

hig

h

end (

5 p

sig)

to e

nsu

re c

onse

rvatism

yet

still

achie

ve t

he

des

ired

res

ults.

11/1

2/2

004

email

Dav

id

Kal

ensk

y Endura

nce

Tes

t •

Prio

r to

the

endura

nce

tes

t, r

egula

tors

should

be

adju

sted

to c

aptu

re d

rift

ove

r tim

e •

Poss

ibly

incl

ude

in t

he

test

reg

ula

tors

that

hav

e nev

er

bee

n in t

he

fiel

d:

1,

5,

10,

and 1

5 y

ears

old

.

• Aft

er s

om

e th

ought,

it

was

dec

ided

that

the

endura

nce

tes

t w

ould

not

pro

vide

any

use

ful

safe

ty p

erfo

rman

ce info

rmat

ion s

ince

we

do

not

know

enough info

rmat

ion a

bout

the

serv

ice

conditio

ns

under

whic

h e

ach

regula

tor

oper

ated

(how

man

y cy

cles

hav

e al

read

y bee

n s

een b

y th

e re

gula

tor?

).

Ther

efore

, it w

as d

ecid

ed t

o r

emove

this

tes

t fr

om

the

regula

tor

test

ing p

roto

col.

Com

men

ts b

ase

d o

n r

egula

tor

test

pro

toco

l in

tern

ally

dis

trib

ute

d o

n 1

1/2

4/2

004 a

nd e

xter

nally

dis

trib

ute

d o

n 1

2/0

8/2

004 (

Att

achm

ent

2)

12/0

9/2

004

email

Jim

Pet

erse

n

2-s

tage

Reg

ula

tors

Will

cer

tain

ly b

e par

t of

the

popula

tion;

test

per

the

single

sta

ge

criter

ia b

ut

in a

sep

arat

e ca

tegory

. 03/2

0/2

005

Em

ail

Jeff

Bort

on

2-s

tage/

Reg

ula

tors

The

test

pro

toco

l does

not

incl

ude

inte

gra

l tw

o-s

tage

regula

tors

or

auto

mat

ic c

han

geo

ver

regula

tors

– w

hy

hav

e th

ese

bee

n lef

t out?

• Agre

e •

Left

out

sole

ly d

ue

to s

pac

e lim

itat

ions

on

the

flow

char

t

12/0

9/2

004

email

Jim

Pet

erse

n

Flow

Tes

ts

• 80 &

200 c

fh a

ir f

low

rat

e is

OK (

ques

tioned

if

usi

ng a

m

ass

flow

met

er o

r re

gula

tor

with f

ixed

ori

fice

) •

Reg

ula

tor

should

be

test

ed in t

he

horizo

nta

l posi

tion f

or

uniform

ity

• Rec

ord

pre

ssure

aft

er it

has

stab

ilize

d a

nd n

ote

pre

ssure

sw

ings

(cyc

ling)

or

nois

e (h

um

min

g)

– p

ress

ure

cyc

ling

in e

xces

s of

that

state

d in U

L 144 2

2.1

.1 s

hall

be

cause

fo

r re

ject

ion

• D

o N

OT u

se inte

rnal

pre

ssure

tap

s on r

egula

tor

• M

onitor

vent

for

any

dis

char

ge

– a

ny

flow

thro

ugh v

ent

during f

low

tes

ts s

hould

be

cause

for

reje

ctio

n

• Run a

n e

xtra

flo

wra

te a

t 1 c

fh t

o m

imic

pilo

t lig

ht

flow

12/1

5/2

004

email

Jim

Gri

ffin

Fl

ow

Tes

ts

• W

e hav

e to

be

care

ful of

the

two f

low

s pic

ked (

80 c

fh &

200 c

fh)

– s

mall,

2nd s

tage

regula

tors

may

only

be

rate

d

to 1

00 o

r 150 s

cfh;

should

ver

ify

man

ufa

cture

r’s

rate

d

capac

itie

s.

12/1

6/2

004

Em

ail

Ron C

zisc

hke

Fl

ow

Tes

ts

• Sta

rt w

ith m

id-i

nle

t pre

ssure

; fo

llow

ed b

y lo

w inle

t pre

ssure

; fo

llow

ed b

y m

ax inle

t pre

ssure

Eac

h s

ample

will

hav

e flow

curv

es g

ener

ated

• W

e w

ill b

e usi

ng a

flo

w m

eter

to m

easu

re t

he

flow

rat

es.

• The

flow

rate

will

be

limited

to a

max

of

80

cfh (

200,0

00 B

TU

/hr)

for

all re

gula

tors

– t

his

re

pre

sents

a t

ypic

al hig

h f

low

rat

e fo

r re

siden

tial sy

stem

s.

• The

outlet

pre

ssure

at

a flow

rat

e of

0.5

cfh

w

ill b

e re

cord

ed t

o r

epre

sent

pilo

t lig

ht

flow

s •

We

will

rec

ord

evi

den

ce o

f hum

min

g/

chat

teri

ng o

r outlet

pre

ssure

inst

abili

ty

(pre

ss.

fluc.

> 0

.5”

WC p

er U

L 144 2

2.1

.1)

• The

regula

tor

vent

will

be

monitore

d f

or

dis

char

ge

during t

he

Lock

-up/F

low

tes

ts –

an

y dis

char

ge

will

be

docu

men

ted

• In

tern

al p

ress

ure

tap

s w

ill N

OT b

e use

d

• Fo

r 1

st s

tage

and s

ingle

sta

ge

regula

tors

te

sts

will

sta

rt a

t 100 p

sig,

then

25 p

sig,

then

250 p

sig –

rep

rese

nting a

typ

ical pre

ss.,

lo

w p

ress

., a

nd h

igh p

ress

. se

quen

ce.

Additio

nally

, th

e firs

t te

st a

t 100 p

sig w

ill

star

t at

a t

ypic

al r

esid

ential flow

of

30 c

fh

(75,0

00 B

TU

/hr)

to a

dju

st t

he

regula

tor;

su

bse

quen

t te

sts

will

sta

rt a

t 80 c

fh

• Fo

r 2

nd s

tage

regula

tors

the

test

s w

ill s

tart

at

10 p

sig,

then

5 p

sig,

then

15 p

sig.

Additio

nally

, th

e firs

t te

st a

t 10 p

sig w

ill s

tart

at

a t

ypic

al re

siden

tial

flo

w o

f 30 c

fh (

75,0

00

BTU

/hr)

to a

dju

st t

he

regula

tor;

subse

quen

t

Page 162: Performance, Durability, and Service Life of Low Pressure ... · Performance, Durability, and Service Life of vii September 2006 Low Pressure Propane Vapor Regulators Battelle Of

Co

mm

en

ts o

n r

eg

ula

tor

test

pro

toco

l an

d a

sso

ciate

d j

ust

ific

ati

on

fo

r th

e r

evis

ed

pro

toco

l

Page

B-2

Date

C

om

men

t Fo

rmat

Co

mm

en

ter

Co

mm

en

t R

ela

ted

to

Co

mm

en

t R

esp

on

se (

Lead

ing

to

th

e f

inal te

st

pro

toco

l –

Att

ach

men

t 3

) te

sts

will

sta

rt a

t 80 c

fh.

12/1

6/2

004

Em

ail

Ron C

zisc

hke

In

form

atio

n

Tag

s •

Info

rmat

ion o

n w

hat

typ

e of sy

stem

the

regula

tor

cam

e fr

om

should

be

reco

rded

12/1

6/2

004

Em

ail

&

Fax

Sam

McT

ier

Info

rmat

ion

Tag

s •

Add “

inte

gra

l tw

o s

tage,

auto

mat

ic c

han

geo

ver,

and h

igh

pre

ssure

” under

“In

dic

ate

Reg

ula

tor

Typ

e”

• U

nder

“ye

ar inst

alle

d”

subst

itute

“M

onth

/Yea

r” f

or

“Dat

e”

and d

elet

e “(

must

be

within

pas

t m

onth

)”

• U

nder

“sh

ippin

g inst

ruct

ions”

ther

e is

not

a good r

easo

n

for

plu

ggin

g a

nd t

apin

g o

ver

regula

tor

port

s or

putt

ing

the

regula

tors

in m

ore

than

1 z

ip-l

ock

bag

.

• M

any

of

the

com

men

ts c

ame

afte

r m

ost

of

the

info

rmat

ion t

ags

had

bee

n s

ent

out.

W

e fe

el t

hat

the

info

rmat

ion t

ags

wer

e su

ffic

ient

to g

ather

the

nec

essa

ry info

rmat

ion a

bout

each

reg

ula

tor.

U

nfo

rtunat

ely,

many

of

the

tags

we

hav

e re

ceiv

ed b

ack

are

not

com

ple

tely

fill

ed in.

• W

e w

ante

d t

o p

lug o

r ta

pe

ove

r th

e port

s to

m

inim

ize

any

odor

rele

ase

duri

ng s

hip

men

t.

12/0

9/2

004

email

Jim

Pet

erse

n

Leaka

ge

Tes

t •

Leak

tes

t sh

ould

be

the

final te

st s

ince

it

utiliz

es t

he

hig

hes

t pre

ssure

s •

Consi

der

addin

g a

pre

ssure

dec

ay (

low

pre

ssure

lea

k)

test

aft

er t

he

lock

up t

est

by

shutt

ing o

ff t

he

upst

ream

pre

ssure

sourc

e 12/1

5/2

004

email

Jim

Gri

ffin

Le

aka

ge

Tes

t •

Not

a fa

n o

f th

e U

L 144 lea

kage

test

for

what

we

are

tryi

ng t

o d

o –

the

UL

test

is

use

d t

o v

alid

ate

join

t se

al

and c

asin

g inte

grity

. •

To p

erfo

rm t

he

test

you m

ust

def

eat

the

safe

ty

mec

han

ism

s in

the

regula

tor.

When

you b

lock

a v

ent

you w

ill m

ost

lik

ely

get

lea

kage

out

of

the

closi

ng c

ap o

f al

l re

gula

tors

at

the

pre

ssure

s su

gges

ted.

• A m

ore

acc

ura

te t

est

is t

o look

for

exte

rnal le

akag

e at

lo

ck-u

p;

or

to b

e m

ore

sev

ere

at ~

90%

of

the

relie

f va

lve

rese

al pre

ssure

. T

his

is

more

typ

ical of

what

a

regula

tor

exper

ience

s day

to d

ay a

nd s

till

valid

ate

s th

e pre

ssure

inte

gri

ty o

f th

e ca

sings

without

the

undue

stre

sses

. 12/1

6/2

004

Em

ail

Dav

id

Sta

inbro

ok

Leak

age

Tes

t •

No r

easo

n t

o b

lock

the

PRD

to t

est

inte

gri

ty o

f th

e at

mosp

her

ic s

ide

of

bonnet

. •

This

is

a des

ign t

est

not

a per

form

ance

tes

t; s

hould

be

inte

rest

ed in p

erfo

rman

ce n

ot

des

ign a

s qual

ifie

d b

y U

L.

• Rec

om

men

ds

a le

akag

e te

st t

o b

e co

nduct

ed a

t a

pre

ssure

just

under

the

allo

wed

min

imum

PRD

set

ting

per

UL

144 (

ex.

1st &

sin

gle

sta

ge

could

be

test

ed a

t 18”W

C b

ack

pre

ssure

) 12/1

6/2

004

Em

ail

Ron C

zisc

hke

Le

aka

ge

Tes

t •

Rea

lizes

that

the

regula

tor

should

hav

e th

e re

lief

valv

e blo

cked

per

UL

144 1

8.3

how

ever

in s

om

e ca

ses

the

man

ufa

cture

r does

not

giv

e th

em s

uch

a s

am

ple

– in

those

case

s th

e ve

nt

open

ing is

plu

gged

, an

d u

nder

this

co

nditio

n,

any

leak

age

at t

he

bonnet

cap

is

dis

regar

ded

. 03/2

0/2

005

Em

ail

Jeff

Bort

on

Leaka

ge

Tes

t •

Leak

age

test

should

be

per

form

ed a

t th

e lo

ck-u

p

pre

ssure

. T

he

pro

pose

d m

ethod d

oes

not

corr

ectly

test

th

e dia

phra

gm

or

PRD

for

leaka

ge

and e

xpose

s th

e re

gula

tor

bonnet

and c

ap t

o p

ress

ure

s, w

hic

h d

o n

ot

occ

ur

in U

L te

sts

or

actu

al use

. 12/1

6/2

004

Em

ail

&

Sam

McT

ier

Leaka

ge

Tes

t •

Sea

l th

e bonnet

cap

with a

sea

l w

asher

and p

ress

urize

• Bas

ed o

n m

any

of

the

com

men

ts r

ecei

ved,

we

hav

e dec

ided

to e

limin

ate

the

leak

age

test

as

des

crib

ed in t

he

12/0

8/2

004 t

est

pro

toco

l.

• In

stea

d,

we

have

dec

ided

to c

hec

k fo

r le

aks

during t

he

Lock

-up T

est

by

blo

ckin

g in t

he

regula

tor

duri

ng t

he

initia

l lo

ck-u

p t

est

at

100 p

sig f

or

1st a

nd s

ingle

sta

ge

and 1

0 p

sig

for

2nd s

tage.

As

stat

ed b

y Ji

m P

eter

sen,

Jim

G

riff

in,

and D

avi

d S

tain

bro

ok

this

tes

t is

m

ore

rep

rese

nta

tive

of

regula

tor

per

form

ance

rat

her

than r

egula

tor

des

ign

whic

h t

he

origin

al lea

kage

test

pro

toco

l ad

dre

ssed

.

Page 163: Performance, Durability, and Service Life of Low Pressure ... · Performance, Durability, and Service Life of vii September 2006 Low Pressure Propane Vapor Regulators Battelle Of

Co

mm

en

ts o

n r

eg

ula

tor

test

pro

toco

l an

d a

sso

ciate

d j

ust

ific

ati

on

fo

r th

e r

evis

ed

pro

toco

l

Page

B-3

Date

C

om

men

t Fo

rmat

Co

mm

en

ter

Co

mm

en

t R

ela

ted

to

Co

mm

en

t R

esp

on

se (

Lead

ing

to

th

e f

inal te

st

pro

toco

l –

Att

ach

men

t 3

) Fa

x th

e body

and b

onnet

with t

he

pre

ssure

s sh

ow

n in t

he

flow

sch

emat

ic a

nd c

hec

k fo

r le

aks

in t

he

dia

phra

gm

sea

l or

from

the

body

or

bonnet

with a

n a

ccep

table

lea

k det

ection s

olu

tion.

• The

pre

ssure

open

s th

e PRV s

o t

he

sam

e pre

ssure

is

found in t

he

body

and b

onnet

are

a.

12/0

9/2

004

email

Jim

Pet

erse

n

Lock

-up T

ests

Lock

up t

est

must

be

final

flo

w t

est

since

it

may

be

des

truct

ive.

Rec

ord

initia

l lo

ckup &

pre

ssure

aft

er 1

min

ute

& 5

m

inute

s (n

ote

any

flow

thro

ugh v

ent)

Usi

ng U

L 144 f

or

“fai

lure

” cr

iter

ia m

ay b

e to

o h

arsh

sin

ce

hig

h lock

ups

are

not

an iss

ue

with p

ilote

d s

yste

ms

(hen

ce t

he

1 c

fh f

low

tes

t).

How

ever

, so

me

criter

ia h

as

to b

e use

d a

nd U

L 144 is

as g

ood a

s an

y 12/1

5/2

004

Em

ail

Jim

Gri

ffin

Lo

ck-u

p T

ests

UL

144 S

ection 2

5.4

use

s 250 p

si inle

t pre

ssure

for

a lo

ck-u

p t

est

– t

his

tes

t is

only

goin

g t

o m

easu

re t

he

inle

t se

nsi

tivi

ty o

f th

e re

gula

tor.

W

hile

it

may

be

a va

lid t

est

for

des

ign,

regula

tors

will

not

exper

ience

this

conditio

n

under

norm

al oper

atin

g c

onditio

ns;

only

if

the

1st s

tage

fails

on a

n e

xtre

mel

y hot

day

. 12/2

8/2

004

Em

ail

Gar

y Koch

Lo

ck-u

p T

ests

Bas

ed o

n e

xper

ience

, a

gre

at m

ajority

of

low

pre

ssure

(1

1”

WC)

outlet

reg

ula

tors

will

lock

-up b

elow

16”

WC –

w

hen

insp

ecte

d t

he

resi

lient

dis

c w

ill h

ave

inden

tations

but

not

dam

age

that

would

cau

se f

ailu

re

• Reg

ula

tors

tes

ted t

o lock

-up p

ress

ure

s >

20”

WC,

the

dis

cs a

re b

adly

inden

ted o

r hav

e ev

iden

ce o

f fo

reig

n

mat

eria

l im

bed

ded

in t

he

surf

ace

with d

am

age

to t

he

exte

nt

that

I co

uld

not

just

ify

the

regula

tor

rem

ain

ing in

serv

ice.

Bas

ed o

n t

he

AN

SI

stan

dar

d a

nd e

xper

ience

, th

inks

that

it w

ould

be

impro

per

to a

ccep

t a

stan

dar

d f

or

regula

tors

to

rem

ain

in s

ervi

ce t

hat

hav

e a

lock

-up p

ress

ure

above

20”

WC f

or

any

low

pre

ssure

reg

ula

tor

• Fe

els

it w

ould

be

difficu

lt t

o just

ify

an a

ccep

table

lock

-up

pre

ssure

bas

ed o

n t

he

relie

f va

lve

max

imum

dis

char

ge

since

this

is

a lim

it e

stab

lished

on t

he

regula

tor

not

oper

atin

g p

roper

ly

• Fo

r 1

st s

tage

regula

tors

– t

esting a

t 25 p

sig is

not

nec

essa

ry s

ince

we

know

lock

-up w

ill b

e gre

ater

at

100

and 2

50 p

sig

• Fo

r 2

nd s

tage

regula

tors

– t

esting a

t 5 a

nd 1

0 p

sig is

not

nec

essa

ry;

inle

t flow

of

15 p

sig is

more

consi

sten

t w

ith

the

max

outlet

fro

m 1

st s

tage

regula

tors

and 2

50 p

sig

would

giv

e re

sults

when

ther

e is

a p

oss

ible

fai

lure

of

the

1st s

tage

regula

tor.

Outlet

pre

ssure

should

be

reco

rded

for

a hig

h f

low

rat

e th

en d

ecre

ase

to a

min

imum

flo

w (

pilo

t flow

- ~

0.2

cf

h/5

00 B

TU

/hr)

– w

ant

to k

now

of

any

hig

h o

utlet

• M

any

voic

ed c

once

rn t

hat

our

criter

ia f

or

“fai

lure

” in

the

12/0

8/2

003 t

est

pro

toco

l (l

ock

-up >

PRD

sta

rt-t

o-d

isch

arge

pre

ssure

) w

as t

oo h

igh a

nd w

ould

com

pro

mis

e sa

fety

.

Man

y m

entioned

that

hig

her

pre

ssure

s w

ould

co

mpro

mis

e th

e in

tegri

ty o

f th

e re

silie

nt

dis

c poss

ibly

causi

ng p

erm

anen

t dam

age;

oth

ers

men

tioned

that

hig

her

lock

-up p

ress

ure

s co

uld

blo

w o

ut

pilo

t lig

hts

. W

e ag

ree

with

thes

e co

mm

ents

and h

ave

revi

sed t

he

“fai

lure

” cr

iter

ia t

o b

e th

e sa

me

as

that

liste

d

in U

L 144 T

able

21.1

. •

The

Lock

-up/F

low

Tes

ts w

ill b

e th

e firs

t te

st

afte

r th

e vi

sual in

spec

tion:

1.

It is

less

des

truct

ive

2.

Allo

ws

us

to c

hec

k th

e in

itia

l outlet

pre

ssure

set

ting o

f th

e re

gula

tor

and w

e ca

n t

hen

adju

st t

he

regula

tor

to t

he

man

ufa

cture

r’s

spec

ifie

d o

utlet

pre

ssure

We

will

use

the

lock

-up p

ress

ure

lim

its

spec

ifie

d in U

L 144 T

able

21.1

as

an

indic

ation o

f re

gula

tor

pro

ble

ms.

We

elim

inate

d t

he

Lock

-up t

est

for

2nd s

tage

regula

tors

at

250 p

sig inle

t pre

ssure

s.

It

was

fel

t th

at t

his

tes

t w

as t

oo e

xtre

me

for

a co

uple

of

reas

ons:

1.

It is

difficu

lt t

o m

ainta

in t

ank

pre

ssure

s of

250 p

sig e

ven o

n e

xtra

ord

inarily

hot

day

s (c

oolin

g f

rom

eva

pora

tion o

f liq

uid

pro

pan

e w

ill k

eep p

ress

ure

s lo

wer

than

this

max

imum

val

ue)

– d

iscu

ssed

by

Sam

M

cTie

r in

12/1

6/2

004 t

elec

onfe

rence

. 2.

This

tes

t re

lies

on t

he

fact

that

the

1st

st

age

regula

tor

fails

– t

his

is

not

a norm

al

oper

atio

nal

/ per

form

ance

iss

ue,

it

is

bas

ed o

n a

n e

xtre

me

situ

atio

n.

• D

uri

ng t

he

initia

l lo

ck-u

p t

ests

(100 p

sig f

or

1st

and s

ingle

sta

ge;

10 p

sig f

or

2nd s

tage)

w

e w

ill b

lock

in t

he

regula

tor

and m

onitor

for

leak

s and f

low

thro

ugh t

he

vent

ove

r a

3-

min

ute

tim

e per

iod –

it

is f

elt

that

this

is

suff

icie

nt

tim

e to

det

erm

ine

pro

ble

ms

with

Page 164: Performance, Durability, and Service Life of Low Pressure ... · Performance, Durability, and Service Life of vii September 2006 Low Pressure Propane Vapor Regulators Battelle Of

Co

mm

en

ts o

n r

eg

ula

tor

test

pro

toco

l an

d a

sso

ciate

d j

ust

ific

ati

on

fo

r th

e r

evis

ed

pro

toco

l

Page

B-4

Date

C

om

men

t Fo

rmat

Co

mm

en

ter

Co

mm

en

t R

ela

ted

to

Co

mm

en

t R

esp

on

se (

Lead

ing

to

th

e f

inal te

st

pro

toco

l –

Att

ach

men

t 3

) pre

ssure

s at

min

flo

w t

hat

could

cause

pro

ble

ms

of

pilo

t outa

ge

or

impro

per

ignitio

n o

f au

tom

atic

gas

ignitio

n

syst

ems

& c

om

ponen

ts.

For

the

0.2

cfh

flo

w –

any

pre

ssure

hig

her

than

16”

WC s

hould

be

consi

der

ed a

s a

failu

re.

• In

let

pre

ssure

should

be

obse

rved

for

2-3

min

ute

s to

as

sure

ther

e is

no c

reep

ing o

f th

e outlet

pre

ssure

; th

en

isola

te t

he

inle

t pre

ssure

to o

bse

rve

the

outlet

pre

ssure

fo

r an

y pre

ssure

dec

ay r

esultin

g f

rom

lea

ks e

ither

at

the

seals

or

thro

ugh t

he

vent;

then

soap

the

regula

tor

exte

rior

and v

ent

to iden

tify

the

sourc

e.

This

tes

t w

ould

not

be

des

truct

ive

and is

more

rep

rese

nta

tive

of

fiel

d

conditio

ns

for

outlet

pre

ssure

s 12/1

6/2

004

Em

ail

Dav

id

Sta

inbro

ok

Lock

-up/F

low

Tes

ts

• O

nce

the

ord

er o

f th

e te

sts

are

changed

(Lo

ck-u

p/F

low

; PR

D;

leak

age)

then

the

par

am

eter

s w

e hav

e la

id o

ut

are

fine

03/2

0/2

005

Em

ail

Jeff

Bort

on

Lock

-up/F

low

Tes

ts

• H

ow

is

it d

eter

min

ed w

het

her

a r

egula

tor

will

be

test

ed

at t

he

resi

den

tial

or

com

mer

cial

flo

w r

ate?

Under

the

failu

re c

rite

ria

for

the

2nd s

tage

250 p

sig t

est,

th

e le

ss t

han

(<

) si

gn s

hould

be

a gre

ater

than

(>

) si

gn.

12/1

6/2

004

Em

ail

&

Fax

Sam

McT

ier

Lock

-up/F

low

Tes

ts

For

1st

and s

ingle

sta

ge

regula

tors

: •

Set

the

inle

t pre

ssure

to 1

00 p

sig w

ith a

flo

w o

f 75,0

00

BTU

/hr

(30 c

fh)

with a

n o

utlet

pre

ssure

of

10 p

sig f

or

1st

st

age

and 1

1”

WC f

or

single

sta

ge

• Then

shutd

ow

n t

he

flow

fro

m t

he

outlet

and r

ecord

the

lock

-up p

ress

ure

to m

ake

sure

it

does

not

exce

ed t

he

max

lock

-up p

ress

ure

in U

L 144

• N

ext

incr

ease

flo

w t

o 2

00,0

00 B

TU

/hr

and 5

00,0

00

BTU

/hr

and r

ecord

the

outlet

pre

ssure

s.

• W

ithout

chan

gin

g t

he

outlet

pre

ssure

set

tings

run t

he

sam

e te

sts

with a

25 p

sig inle

t pre

ssure

and a

200 p

sig

inle

t pre

ssure

An inle

t pre

ssure

of

250 p

sig is

impra

ctic

al t

o s

ust

ain in a

norm

al in

stalla

tion

For

2nd s

tage

regula

tors

: •

Set

the

inle

t pre

ssure

to 1

0 p

sig w

ith a

flo

w o

f 75,0

00

BTU

/hr

(30 c

fh)

with a

n o

utlet

pre

ssure

of

11”

WC

• Then

shutd

ow

n t

he

flow

fro

m t

he

outlet

and r

ecord

the

lock

-up p

ress

ure

to m

ake

sure

it

does

not

exce

ed t

he

max

lock

-up p

ress

ure

in U

L 144

• N

ext

incr

ease

flo

w t

o 2

00,0

00 B

TU

/hr

and 5

00,0

00

BTU

/hr

and r

ecord

the

outlet

pre

ssure

s.

• W

ithout

chan

gin

g t

he

outlet

pre

ssure

set

tings

run t

he

sam

e te

sts

with a

7 ½

psi

g inle

t pre

ssure

Fr

om

Phone

Conve

rsation 1

2/1

6/2

004

• If

lock

-up p

ress

ure

s ar

e to

o h

igh t

hey

could

pote

ntial

ly

blo

w o

ut

a pilo

t lig

ht

– t

his

is

a sa

fety

iss

ue

• N

eed t

o t

est

lock

-up in t

he

range

of

pilo

t lig

ht

flow

s

the

regula

tor

(lea

ks,

pre

ssure

flu

ctuations,

re

lief

venting)

• Lo

ck-u

p t

ests

will

still

be

run a

t th

e 3

pre

ssure

s pre

viousl

y m

entioned

in t

he

12/0

8/2

004 t

est

pro

toco

l; h

ow

ever

the

ord

er

in w

hic

h t

he

pre

ssure

s w

ill b

e te

sted

has

ch

anged

. 1.

1st

sta

ge

and s

ingle

sta

ge

regula

tors

initia

l Lo

ck-u

p/F

low

Tes

t at

100 p

sig,

then

25 p

sig,

then

250 p

sig -

rep

rese

nts

ty

pic

al p

ress

., low

pre

ss.,

and h

igh

pre

ss.

for

the

test

seq

uen

ce.

Additio

nally

, th

e firs

t te

st a

t 100 p

sig

will

sta

rt a

t a

typic

al re

siden

tial

flo

w o

f 30 c

fh (

75,0

00 B

TU

/hr)

to a

dju

st t

he

regula

tor;

subse

quen

t te

sts

will

sta

rt a

t 80 c

fh t

hen

low

er t

o 3

0 c

fh,

0.5

cfh

, an

d

then

lock

-up (

dat

a w

ill b

e ta

ken a

t th

ese

spec

ific

flo

ws)

2.

2nd s

tage

regula

tors

– initia

l Lo

ck-

up/F

low

Tes

t at

10 p

sig,

then

5 p

sig,

then

15 p

sig -

rep

rese

nts

typ

ical

pre

ss.,

lo

w p

ress

., a

nd h

igh p

ress

. fo

r th

e te

st

sequen

ce.

Additio

nally

, th

e firs

t te

st a

t 100 p

sig w

ill s

tart

at

a ty

pic

al re

siden

tial

flow

of

30 c

fh (

75,0

00 B

TU

/hr)

to a

dju

st

the

regula

tor;

subse

quen

t te

sts

will

sta

rt

at 8

0 c

fh t

hen

low

er t

o 3

0 c

fh,

0.5

cfh

, an

d t

hen

lock

-up (

data

will

be

take

n a

t th

ese

spec

ific

flo

ws)

The

low

er f

low

rat

e (0

.5 c

fh)

is c

hose

n t

o

repre

sent

typic

al f

low

s fo

r pilo

t lig

hts

; th

e m

iddle

flo

w o

f 30 c

fh r

epre

sents

typ

ical

re

siden

tial flow

s; a

nd t

he

hig

h f

low

rat

e of

80 c

fh is

chose

n t

o r

epre

sent

typic

al

max

imum

flo

w r

ates

. •

Com

mer

cial

flo

w r

ates

will

not

be

test

ed;

the

max

imum

flo

w r

ate

will

be

80 c

fh.

Page 165: Performance, Durability, and Service Life of Low Pressure ... · Performance, Durability, and Service Life of vii September 2006 Low Pressure Propane Vapor Regulators Battelle Of

Co

mm

en

ts o

n r

eg

ula

tor

test

pro

toco

l an

d a

sso

ciate

d j

ust

ific

ati

on

fo

r th

e r

evis

ed

pro

toco

l

Page

B-5

Date

C

om

men

t Fo

rmat

Co

mm

en

ter

Co

mm

en

t R

ela

ted

to

Co

mm

en

t R

esp

on

se (

Lead

ing

to

th

e f

inal te

st

pro

toco

l –

Att

ach

men

t 3

) 03/2

0/2

005

Em

ail

Jeff

Bort

on

Mate

rial

Tes

ting

• Chan

ges

can o

ccur

to t

he

regula

tor

mate

rial

s of

const

ruct

ion b

ecau

se o

f ag

e an

d e

nvi

ronm

ent;

has

m

ater

ial te

stin

g b

een c

onsi

der

ed t

o f

urt

her

under

stand if

deg

radat

ion h

as

occ

urr

ed d

ue

to h

arsh

envi

ronm

ents

?

• N

o

12/0

9/2

004

Em

ail

Jim

Pet

erse

n

PRD

Tes

ts

• M

ust

be

afte

r flow

tes

ts s

ince

it

may

be

des

truct

ive

(may

not

be

repea

table

due

to s

eal ad

hes

ion)

12/1

6/2

004

Em

ail

Dav

id

Sta

inbro

ok

PRD

Tes

ts

• Should

be

more

conce

rned

about

when

the

PRD

sta

rts

to

dis

char

ge

and w

hen

it

rese

ats

than w

ith r

elie

f flow

ca

pac

ity

• The

use

of

soap s

olu

tion t

o m

easu

re w

hen

a P

RD

open

s an

d r

esea

ls is

not

the

bes

t ch

oic

e:

1.

For

2nd a

nd s

ingle

sta

ge

a w

ate

r m

anom

eter

should

be

inst

alle

d a

t th

e outlet

with b

ack

pre

ssure

slo

wly

ap

plie

d.

When

the

PRD

open

s, t

he

man

om

eter

will

st

op r

isin

g.

Sto

p b

ack

pre

ssure

, th

e m

anom

eter

will

dro

p b

ut

stops

when

res

eal is

ach

ieve

d.

2.

1st s

tage

regula

tors

will

use

a p

ress

ure

gau

ge

rath

er

than

man

om

eter

and f

ollo

w t

he

sam

e pro

cess

as

above

A n

um

ber

of

1st s

tage

regula

tors

will

not

have

an inte

gra

l PRD

(no N

FPA 5

8 o

r U

L 144 r

equir

emen

t until 1995)

12/1

6/2

004

Em

ail

Ron C

zisc

hke

PRD

Tes

ts

• M

inim

um

flo

w f

or

a Typ

e I

dev

ice

is 4

0D

P w

ith D

bei

ng

no les

s th

an 1

/8”

12/1

6/2

004

Em

ail

&

Fax

Sam

McT

ier

PRD

Tes

ts

• Chec

k th

e PR

V o

pen

ing a

nd c

losi

ng p

ress

ure

s by

atta

chin

g a

lin

e w

ith a

res

tric

tive

ori

fice

to t

he

outlet

of

each

reg

ula

tor.

Slo

wly

rais

e th

e pre

ssure

to o

utlet

until th

e PR

V o

pen

s –

reco

rd t

he

pre

ssure

to e

nsu

re it

is w

ithin

the

limits

show

n in U

L 144.

• Then

shutd

ow

n t

he

flow

to t

he

outlet

and r

ecord

the

PRV

closi

ng p

ress

ure

You d

o n

ot

nee

d t

o u

se s

oap

y w

ater

– just

look

at t

he

pre

ssure

gau

ge

• W

e do n

ot

nee

d t

o k

now

the

flow

rat

e of

the

PRVs

• The

only

rea

l co

nce

rn is

that

the

outlet

pre

ssure

of

2nd

stag

e re

gula

tors

nev

er e

xcee

ds

2 p

sig w

ith t

ota

l se

at

failu

re w

ith a

15 p

sig inle

t pre

ssure

12/1

6/2

004

Em

ail

Dav

id

Sta

inbro

ok

PRD

Tes

ts

• Rel

ief

flow

cap

acity

dat

a is

of

little

valu

e fo

r per

form

ance

te

stin

g (

more

for

des

ign).

03/2

0/2

005

Em

ail

Jeff

Bort

on

PRD

Tes

ts

• The

low

sid

e fa

ilure

cri

teria

for

the

PRD

s-t

-d o

f <

140%

fo

r 1

st s

tage

and <

170%

for

single

and 2

nd s

tage

regula

tors

should

be

repla

ced w

ith t

he

requirem

ent

that

the

s-t-

d m

ust

be

> t

han t

he

lock

-up p

ress

ure

. •

The

PRD

res

et p

ress

ure

fai

lure

crite

ria

should

be

repla

ced w

ith t

he

requirem

ent

that

the

rese

t pre

ssure

m

ust

be

gre

ater

than t

he

lock

up p

ress

ure

for

that

in

div

idual

reg

ula

tor.

The

hig

h s

ide

failu

re c

rite

ria

for

the

PRD

s-t

-d a

re

• M

any

com

men

ters

voic

ed c

once

rn a

bout

usi

ng a

soap

y w

ater

solu

tion t

o d

etec

t th

e PR

D s

tart

-to-d

isch

arge

pre

ssure

: 1.

Too d

ifficu

lt t

o d

eter

min

e s-

t-d b

ased

on

a bubble

solu

tion

2.

The

initia

l bubble

mig

ht

not

be

the

actu

al

s-t-

d b

ut

the

dia

phra

gm

movi

ng c

ausi

ng

flow

out

of

the

spring c

asin

g

• Bec

ause

of

this

conce

rn w

e have

dec

ided

to

use

a p

ress

ure

tra

nsd

uce

r to

iden

tify

the

s-t-

d p

ress

ure

(fo

r 2

nd s

tage

regula

tors

it

may

la

ter

be

dec

ided

to u

se a

wat

er m

anom

eter

to

det

ect

the

low

er p

ress

ure

chan

ges

) •

Although a

num

ber

of

com

men

ters

m

entioned

that

they

see

no n

eed t

o m

easu

re

the

relie

f flow

cap

acity,

we

will

continue

to

mea

sure

it

as

par

t of

the

1st a

nd s

ingle

sta

ge

PRD

tes

ts.

It

at

least

pro

vides

anoth

er d

ata

poin

t and w

e don’t f

eel th

at it

will

co

mpro

mis

e th

e te

sts

in a

ny

way

. W

e fe

el

that

if a

pre

ssure

rel

ief dev

ice

does

not

hav

e su

ffic

ient

flow

, th

en t

her

e is

a p

roble

m w

ith

its

relie

ving c

apac

ity

and p

ote

ntially

re

gula

tor

safe

ty.

• In

the

test

pro

toco

l se

nt

out

on 1

2/0

8/2

004

we

state

d t

hat

for

1st a

nd s

ingle

sta

ge

regula

tors

we

would

continue

to r

aise

the

pre

ssure

to 5

psi

g a

bove

the

s-t-

d p

ress

ure

to

mea

sure

rel

ief

flow

cap

aci

ty.

Aft

er m

uch

dis

cuss

ion,

we

hav

e dec

ided

that

3 p

sig

above

the

s-t-

d p

ress

ure

is

suff

icie

nt

to

reco

rd t

he

nec

essa

ry f

low

dat

a.

• The

hig

h s

ide

failu

re c

rite

ria

will

be

base

d o

n

the

man

ufa

cture

rs o

utlet

pre

ssure

as

we

hav

e now

dec

ided

to a

dju

st t

he

regula

tors

prior

to t

esting;

ther

efore

the

sele

cted

cr

iter

ia s

hould

still

be

valid

. •

Agre

e w

ith J

eff’s

last

com

men

t; w

e w

ill n

ot

be

mea

suri

ng r

elie

f flow

for

2nd s

tage

regula

tors

.

Page 166: Performance, Durability, and Service Life of Low Pressure ... · Performance, Durability, and Service Life of vii September 2006 Low Pressure Propane Vapor Regulators Battelle Of

Co

mm

en

ts o

n r

eg

ula

tor

test

pro

toco

l an

d a

sso

ciate

d j

ust

ific

ati

on

fo

r th

e r

evis

ed

pro

toco

l

Page

B-6

Date

C

om

men

t Fo

rmat

Co

mm

en

ter

Co

mm

en

t R

ela

ted

to

Co

mm

en

t R

esp

on

se (

Lead

ing

to

th

e f

inal te

st

pro

toco

l –

Att

ach

men

t 3

) def

ined

as

a %

of

the

outlet

pre

ssure

. S

ince

outlet

pre

ssure

s w

ill b

e “a

s re

ceiv

ed”

and n

ot

rese

t, t

he

outlet

pre

ssure

use

d h

ere

must

be

the

actu

al outlet

pre

ssure

of

each

indiv

idual

reg

ula

tor,

not

the

set

valu

e use

d in

UL1

44.

• Per

UL1

44 t

her

e is

no P

RD

flo

wra

te r

equir

emen

t fo

r 2

nd

stag

e re

gula

tors

with t

ype

2 P

RD

s.

The

2nd s

tage

PRD

flow

rate

should

not

be

test

ed a

s th

is d

ata

has

no

pas

s/fa

il cr

iter

ia.

12/2

8/2

004

Em

ail

Gar

y Koch

PRD

Tes

ts

• Should

def

ine

the

pre

ssure

rel

ief

valv

e dis

char

ged

not

as

when

the

1st b

ubble

appea

rs f

rom

the

vent

but

when

a

stea

dy

stre

am o

f bubble

s/flow

is

obse

rved

. I

nte

rmitte

nt

or

the

1st b

ubble

may

only

indic

ate

that

the

dia

phra

gm

is

movi

ng in a

n u

pw

ard p

osi

tion t

o c

ause

flo

w o

ut

of

the

spring c

ase.

12/1

6/2

004

Em

ail

Dav

id

Sta

inbro

ok

Reg

ula

tor

Adju

stm

ent

• M

any

of

the

UL

refe

rence

par

amet

ers

are

base

d o

ff t

he

regula

tor

set

poin

t.

You w

ill f

ind a

num

ber

of

regula

tors

w

her

e th

e ad

just

ing s

crew

has

bee

n c

hanged

for

exam

ple

to c

om

pen

sate

for

exce

ssiv

e pre

ssure

dro

p in

the

syst

em.

If y

ou d

on’t e

stablis

h a

consi

sten

t se

t poin

t,

the

data

you g

ener

ate

will

be

all ove

r th

e pla

ce.

1.

Set

sin

gle

sta

ge

to 1

1”

WC d

eliv

ery

@ 7

5,0

00 B

TU

(3

0 c

fh)

at

75 p

sig inle

t 2.

Set

2nd s

tage

to 1

1”

WC d

eliv

ery

@ 7

5,0

00 B

TU

(30

cfh)

at

10 p

sig inle

t 3.

Set

2nd s

tage,

lar

ge

capac

ity

to 1

1”

WC d

eliv

ery

@

100,0

00 B

TU

(40 c

fh)

at 1

0 p

sig inle

t 4.

Set

1st s

tage

to 1

0,

15

, o

r 2

0 p

sig

(b

ase

d o

n

mo

del #

) @

200,0

00 B

TU

(80 c

fh)

at 1

00 p

sig inle

t •

Not

ever

y m

anufa

cture

r se

ts t

he

regula

tors

the

sam

e w

ay;

the

capaci

ty o

f th

e re

gula

tor

can a

ffec

t how

the

set

poin

t is

det

erm

ined

. •

Without

an a

ccura

te s

et p

oin

t yo

ur

dat

a w

ill b

e su

spec

t.

12/1

6/2

004

Em

ail

Ron C

zisc

hke

Reg

ula

tor

Adju

stm

ent

• D

o n

ot

adju

st t

he

regula

tor

- dis

agre

ed w

ith S

am M

cTie

r

12/1

6/2

004

Em

ail

&

Fax

Sam

McT

ier

Reg

ula

tor

Adju

stm

ent

• All

regula

tors

are

req

uired

to b

e m

arke

d b

y th

e m

anufa

cture

r w

ith t

he

outlet

pre

ssure

set

ting.

• Aft

er t

he

initia

l vi

sual in

spec

tion,

it w

ould

be

nic

e to

note

th

e outlet

pre

ssure

“as

rece

ived

” •

Any

test

s of

the

regula

tor

should

be

done

afte

r th

e re

gula

tor

outlet

pre

ssure

is

adju

sted

to t

he

man

ufa

cture

r’s

mar

ked s

etting;

the

test

s w

ill o

nly

be

mea

nin

gfu

l if t

he

regula

tor

outlet

pre

ssure

is

set

at t

he

man

ufa

cture

r’s

mar

ked s

etting.

• Set

the

regula

tors

in t

he

Lock

-up/F

low

Tes

ts:

1.

For

1st,

single

sta

ge,

auto

mat

ic c

han

geo

ver

and

inte

gra

l 2-s

tage;

set

the

inle

t pre

ssure

to 1

00 p

sig

with a

flo

w o

f 75,0

00 B

TU

/hr

(30 c

fh)

with a

n o

utlet

• O

ur

initia

l th

oughts

in b

oth

the

pro

toco

l dis

trib

ute

d o

n 1

1/0

4/2

004 a

nd 1

2/0

8/2

004

wer

e to

not

adju

st t

he

regula

tors

prior

to

test

ing.

The

thin

king invo

lved

the

fact

that

w

e did

not

wan

t to

tam

per

with t

he

regula

tors

in a

ny

way

that

mig

ht

jeopar

diz

e th

e te

stin

g r

esults.

• Aft

er m

any

dis

cuss

ions

and c

om

men

ts f

rom

th

ose

invo

lved

, w

e hav

e re

consi

der

ed a

nd

dec

ided

that

it w

ould

be

bes

t to

adju

st t

he

regula

tors

to t

he

manufa

cture

r sp

ecifie

d

outlet

pre

ssure

prior

to t

esting.

• The

pro

cedure

is

as f

ollo

ws:

1.

For

1st a

nd s

ingle

sta

ge

regula

tors

: st

art

with a

n inle

t pre

ssure

of

100 p

sig (

per

UL

144 S

ection 1

7.3

) an

d f

low

rat

e of

30 c

fh

(75,0

00 B

TU

/hr)

– r

epre

senting a

vera

ge

pre

ssure

s and f

low

rat

es t

hat

a r

egula

tor

may

exp

erie

nce

ove

r a

year

. 2.

For

2nd s

tage

regula

tors

: st

art

with a

n

inle

t pre

ssure

of

10 p

sig (

per

UL

144

Sec

tion 1

7.3

) an

d f

low

rat

e of

30 c

fh

(75,0

00 B

TU

/hr)

– r

epre

senting a

vera

ge

pre

ssure

s and f

low

rat

es t

hat

a r

egula

tor

may

exp

erie

nce

ove

r a

year

. 3.

Note

the

initia

l outlet

pre

ssure

s bef

ore

an

y re

gula

tor

adju

stm

ent

is p

erfo

rmed

4.

Adju

st t

he

regula

tor

to t

he

man

ufa

cture

r sp

ecifie

d o

utlet

pre

ssure

(si

ngle

and

seco

nd s

tage

11”

WC;

1st s

tage

10,

15 o

r 20 p

sig)

and c

ontinue

with L

ock

-up/F

low

te

st s

tart

ing a

t 30 c

fh,

then

0.5

cfh

, th

en

lock

-up.

Page 167: Performance, Durability, and Service Life of Low Pressure ... · Performance, Durability, and Service Life of vii September 2006 Low Pressure Propane Vapor Regulators Battelle Of

Co

mm

en

ts o

n r

eg

ula

tor

test

pro

toco

l an

d a

sso

ciate

d j

ust

ific

ati

on

fo

r th

e r

evis

ed

pro

toco

l

Page

B-7

Date

C

om

men

t Fo

rmat

Co

mm

en

ter

Co

mm

en

t R

ela

ted

to

Co

mm

en

t R

esp

on

se (

Lead

ing

to

th

e f

inal te

st

pro

toco

l –

Att

ach

men

t 3

) pre

ssure

of

10 p

sig f

or

1st s

tage

and 1

1”

WC f

or

single

sta

ge,

auto

mat

ic c

han

geo

ver,

and inte

gra

l 2-

stag

e 2.

For

2nd s

tage;

set

the

inle

t pre

ssure

to 1

0 p

sig w

ith

a flow

of

75,0

00 B

TU

/hr

(30 c

fh)

with a

n o

utlet

pre

ssure

of

11”

WC

Set

tings

for

Max.

Cap

acity

Rat

ings

(Fax

) 1.

Sin

gle

sta

ge,

inte

gra

l 2-s

tage,

and a

uto

matic

chan

geo

ver:

set

the

inle

t pre

ssure

to 2

5 p

sig w

ith a

m

inim

um

outlet

pre

ssure

set

ting o

f 10”

WC (

9”

alte

rnative

and r

ever

se s

ide

for

auto

matic

chan

geo

ver)

2.

1st s

tage:

set

the

inle

t pre

ssure

to 2

5 p

sig w

ith a

m

inim

um

outlet

pre

ssure

set

ting o

f 7.5

psi

g

3.

2nd s

tage:

set

the

inle

t pre

ssure

to 7

.5 p

sig w

ith a

m

inim

um

outlet

pre

ssure

set

ting o

f 10”

WC (

9”

alte

rnative

)

5.

Blo

ck-i

n t

he

regula

tor

to c

hec

k fo

r le

aks

and/o

r pre

ssure

dec

ay o

ver

a 3

-min

ute

per

iod

6.

Open

inle

t va

lve

and a

dju

st f

low

up t

o t

he

max

imum

flo

w r

ate

of

80 c

fh

7.

Continue

with L

ock

-up/F

low

tes

ts w

ithout

furt

her

adju

stm

ent

to r

egula

tor

12/1

6/2

004

Em

ail

&

Fax

Sam

McT

ier

Rep

ort

ing

• W

e sh

ould

kee

p t

rack

of

the

# o

f re

gula

tors

rec

eive

d

that

hav

e noth

ing w

rong w

ith t

hem

and t

hei

r per

centa

ge

of

the

tota

l #

of

regula

tors

rec

eive

d

• A b

reak

dow

n o

f w

hy

regula

tors

hav

e fa

iled s

hould

be

clea

rly

stat

ed

• W

e w

ill d

ocu

men

t all

findin

gs

from

eac

h

regula

tor

test

ed incl

udin

g p

erfo

rmin

g f

ailu

re

anal

ysis

for

a re

pre

senta

tive

sam

ple

.

12/1

6/2

004

Em

ail

&

Fax

Sam

McT

ier

Saf

ety

Issu

es

• D

oes

n’t k

now

how

we

can s

epar

ate

safe

ty iss

ues

fro

m

per

form

ance

iss

ues

– inad

equat

e or

faile

d p

erfo

rman

ce

of

a pro

pan

e re

gula

tor

usu

ally

lea

ds

to a

ser

ious

safe

ty

issu

e.

• O

K

03/2

0/2

005

Em

ail

Jeff

Bort

on

Sta

tist

ical

Sam

plin

g

• H

ow

is

the

appro

priat

e m

ix o

f re

gula

tors

det

erm

ined

and

contr

olle

d?

The

mix

would

nee

d t

o e

nsu

re a

sta

tist

ically

si

gnific

ant

quantity

is

obta

ined

fro

m v

ario

us

loca

tions,

en

viro

nm

ents

, ap

plic

atio

ns,

and m

anufa

cture

rs.

• W

hat

info

rmation w

as t

he

pro

pan

e m

arke

ter

aske

d t

o

incl

ude?

– m

inim

um

info

rmation s

hould

be

loca

tion o

f use

, en

viro

nm

ent

des

crip

tion,

applic

ation d

escr

iption,

how

oft

en s

ervi

ced,

etc.

• W

e w

ill b

e usi

ng s

tatist

ical an

alys

es (

base

d

on r

egula

tor

age,

man

ufa

cture

r, g

eogra

phic

lo

cation,

type)

to s

elec

t th

e re

gula

tors

for

test

ing.

• Pr

opan

e m

arke

ters

wer

e pro

vided

with

info

rmation t

ags

to f

ill o

ut

with info

rmation

about

the

regula

tor,

its

inst

alla

tion,

and its

use

. 03/0

5/2

005

Em

ail

Jeff

Bort

on

Tes

t Pro

toco

l •

Som

e of

the

test

ing is

per

the

late

st r

evis

ion o

f U

L 144.

Reg

ula

tors

will

lik

ely

hav

e bee

n m

anufa

cture

d t

o a

n

earlie

r ve

rsio

n –

they

should

be

test

ed t

o t

he

applic

able

st

andar

d in p

lace

at

the

tim

e of

man

ufa

cture

r.

12/0

9/2

004

Em

ail

Jim

Pet

erse

n

Tes

t Seq

uen

ce

• Rea

rran

ge

test

ord

er s

o t

hat

the

flow

tes

ts a

re f

irst

, th

en

lock

up,

then

PRV t

ests

, and last

the

leaka

ge

test

12/1

5/2

004

Em

ail

Jim

Gri

ffin

Tes

t Seq

uen

ce

• Str

ongly

rec

om

men

ds

afte

r vi

sual in

spec

tions

that

the

test

ord

er b

e re

arra

nged

as

follo

ws:

1.

Lock

Up/F

low

tes

t 2.

Rel

ief

valv

e te

st

3.

Leak

age

test

Rea

son f

or

change

– t

he

test

met

hod w

ill b

ack

pre

ssure

th

e re

gula

tor

wel

l ab

ove

norm

al o

per

atin

g c

onditio

ns

causi

ng t

he

mai

n d

isc

to c

lose

ver

y tightly

agai

nst

the

• The

origin

al re

gula

tor

test

ing s

equen

ce (

from

12/0

8/2

004 p

roto

col)

invo

lved

: 1.

Vis

ual

insp

ections

(inte

rnal/

exte

rnal)

2.

Leak

age

test

3.

PRD

/Flo

w C

apaci

ty t

est

4.

Lock

-up/F

low

tes

t •

Man

y of

the

com

men

ters

agre

ed t

hat

this

te

st s

equen

ce w

as n

ot

the

bes

t m

ethod f

or

test

ing t

he

regula

tors

. S

om

e of

the

reaso

ns

incl

uded

:

Page 168: Performance, Durability, and Service Life of Low Pressure ... · Performance, Durability, and Service Life of vii September 2006 Low Pressure Propane Vapor Regulators Battelle Of

Co

mm

en

ts o

n r

eg

ula

tor

test

pro

toco

l an

d a

sso

ciate

d j

ust

ific

ati

on

fo

r th

e r

evis

ed

pro

toco

l

Page

B-8

Date

C

om

men

t Fo

rmat

Co

mm

en

ter

Co

mm

en

t R

ela

ted

to

Co

mm

en

t R

esp

on

se (

Lead

ing

to

th

e f

inal te

st

pro

toco

l –

Att

ach

men

t 3

) orifice

. I

t w

ill a

lso o

pen

the

inte

rnal

rel

ief

valv

e as

you

go a

bove

the

set-

poin

t allo

win

g p

ress

ure

into

the

spring

case

com

pro

mis

ing t

he

Lock

-up a

nd P

RV t

ests

. 12/1

6/2

004

Em

ail

Ron C

zisc

hke

Tes

t Seq

uen

ce

• The

ord

er o

f te

stin

g s

hould

be

reve

rsed

: 1.

Flow

/lock

up

2.

Rel

ief

valv

e per

form

ance

3.

Leak

age

test

12/2

8/2

004

Em

ail

Gar

y Koch

Tes

t Seq

uen

ce

• W

ould

not

conduct

tes

ts in t

his

seq

uen

ce s

ince

the

leak

age

test

is

at h

igher

pre

ssure

s an

d is

likel

y to

be

des

truct

ive

(dam

age

to t

he

resi

lient

dis

c)

1.

Lock

-up/F

low

tes

t 2.

PRD

tes

t 12/2

8/2

004

Em

ail

Gar

y Koch

Tes

ting

Req

uirem

ents

The

test

lim

its

should

be

base

d o

n t

he

syst

em in w

hic

h

thes

e re

gula

tors

will

be

inst

alle

d.

• W

e ar

e ta

king r

egula

tors

fro

m s

ervi

ce a

nd m

ost

, if n

ot

all, h

ave

bee

n in a

pplic

atio

ns

wher

e th

ere

is a

sta

ndin

g

pilo

t lig

ht

(wate

r hea

ter)

We

must

consi

der

and e

stab

lish a

ny

acce

pta

ble

tab

le

limit b

ased

on a

pplic

atio

ns

wher

e th

ere

will

be

no

stan

din

g p

ilot

in t

he

futu

re (

furn

aces

; gas

ran

ges

) •

Als

o c

onsi

der

the

AN

SI

stan

dar

ds

that

hav

e es

tablis

hed

pre

ssure

s fo

r te

stin

g c

ontr

ols

and a

pplia

nce

s – A

NSI

Z21.7

8 (

standar

d f

or

com

bin

atio

n g

as c

ontr

ols

for

gas

ap

plia

nce

s) t

he

pre

ssure

giv

en f

or

leak

age

is 2

1”

WC f

or

a st

andar

d 1

1”

WC s

etting

o

The

bac

k-pre

ssure

s ex

per

ience

d in t

he

leak

age

test

could

be

des

truct

ive

to t

he

regula

tor

hen

ce c

om

pro

mis

ing t

he

rem

ain

ing P

RD

and L

ock

-up/F

low

tes

t re

sults.

o

The

pre

ssure

s ex

per

ience

in t

he

PRD

/Flo

w

Cap

acity

Tes

ts w

ill a

lso b

e hig

her

than

th

ose

for

the

lock

-up t

est;

ther

efore

this

sh

ould

be

conduct

ed a

fter

the

Lock

-up/F

low

tes

ts in c

ase

they

are

des

truct

ive.

Bas

ed o

n a

ll of

the

feed

bac

k, w

e ag

ree

that

the

test

seq

uen

ce s

hould

be

reve

rsed

fro

m

that

spec

ifie

d in t

he

12/0

8/2

004 p

roto

col.

Additio

nally

, w

e ag

ree

that

the

UL

144

leak

age

test

is

more

of

a des

ign s

pec

ific

ation

than

a p

erfo

rman

ce s

pec

ific

ation a

nd h

ave

rem

ove

d it

from

the

test

pro

toco

l (s

ee

Leak

age

Tes

t se

ctio

n).

The

new

tes

t se

quen

ce is

as f

ollo

ws:

Vis

ual

Insp

ection (

inte

rnal/

exte

rnal)

Rec

ord

initia

l re

gula

tor

outlet

pre

ssure

Adju

st r

egula

tor

to m

anufa

cture

r sp

ecifie

d

outlet

pre

ssure

Lock

-up/F

low

Tes

ts (

chec

k fo

r le

aks

by

blo

ckin

g in r

egula

tor)

PRD

/Flo

w C

apaci

ty T

ests

12/1

6/2

004

Em

ail

Ron C

zisc

hke

Vis

ual

In

spec

tion

• Should

incl

ude

any

evid

ence

of

conta

min

ants

03/2

0/2

005

Em

ail

Jeff

Bort

on

Vis

ual

In

spec

tion

• A s

et o

f cr

iter

ia s

hould

be

pro

vided

to t

he

per

sonnel

per

form

ing t

he

insp

ection t

o c

onsi

sten

tly

gra

de

and

reco

rd w

hat

they

see

. F

or

exam

ple

, lig

ht

oxi

dat

ion o

r se

vere

corr

osi

on;

visu

al co

rrosi

on s

tandar

ds

mig

ht

be

hel

pfu

l to

obta

in c

onsi

sten

t data

. 12/1

6/2

004

Em

ail

&

Fax

Sam

McT

ier

Vis

ual

In

spec

tion

• If

a b

onnet

cap

is

mis

sing o

n a

reg

ula

tor,

it

should

be

repla

ced a

nd t

he

regula

tor

should

be

test

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APPENDIX C

Inspections of “Failed” Regulators

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Page C-1

Appendix C – Failure Analysis on Selected Regulators Several of the regulators identified as “failures” were selected for detailed failure analysis to determine possible failure mechanisms and environmental variables that contributed to the failure. The regulators selected for failure analysis are presented in the table below. Detailed analyses follow. Regulator

ID Manuf. Age Climate State Service

Area Reason for Removal Reason for not meeting UL

Criteria 13

(2-stage) A 13 Warm,

Damp AL Rural Faulty regulator; no pressure

at regulator outlet High lock-up pressure

42 (second)

B 16 Warm, Dry

IL Suburban End of manufacturer’s recommended service life

High lock-up pressure

72 (second)

A 16 Cool, Dry

CO Rural Tank and regulator removed from service

Chatters and leaks through PRD at 10 psig inlet pressure and 30 cfh.

353 (single)

A 15 Warm, Damp

MS Rural End of manufacturer’s recommended service life

Chatters and leaks through PRD at 100 psig inlet pressure and 30 cfh.

361 (first)

B 27 Warm, Dry

CA Urban Tank and regulator removed from service

PRD start-to-discharge and reseating pressures too low; dirty exterior; clean interior; could not adjust

383 (single)

B 43 Cool, Dry

SD Rural PRD start-to-discharge pressure too high in first trial; high lock-up

490 (2-stage)

B 6 Warm, Damp

FL Suburban Changed from single to dual regulator system

Chatters and leaks through PRD at 100 psig inlet pressure and 30 cfh.

538 (first)

A 16 Warm, Dry

PA Suburban Tank and regulator removed from service

Leak through PRD at 25 psi inlet pressure and 0 cfh; high lock-up pressure

571 (first)

B 10 Cool, Damp

MI Rural Faulty regulator Leaked through PRD during adjustment

711 (second)

A 27 Cool, Dry

SD Rural End of manufacturer’s recommended service life

PRD did not relieve after reaching 65” W.C.

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Failure analysis Regulator #13

Page C-2

Problem

This integral twin stage regulator was removed from service because there was “no pressure at the regulator

outlet”. During testing the regulator exhibited “high lockup”. A representative plot of the data taken during testing

is shown in Figure 1.

Regulator 13 Flow Test - 250 psig Inlet

101112131415161718192021222324

07:00 08:00 09:00 10:00 11:00 12:00 13:00Time (mm:ss)

Out

let P

ress

ure

(inH

2O)

-505101520253035404550556065

Flo

w (c

fm)

Outlet Pressure Flow

Figure 1: Regulator 13 Flow Test

All the medium pressure inlet (100 psig) and high pressure inlet (250 psig) flow tests indicated similar

results. Specifically, at lock-up the outlet pressure gradually increased to approximately 20 in w.c. over a two to

three minute time span. For the low pressure inlet (25 psig) flow test, the outlet pressure remained relatively

constant at lock-up, approximately 12.2 in w.c..

This data suggests that there is a leak path between the inlet and outlet of one of the two stages. A leak

through either stage could cause the same behavior as shown in the plot, either by overpressure on the second-stage

inlet or a direct leak through the second-stage.

Inspection

The outside of the regulator body is in good condition. There is some chipped and scratched paint on the

surface, but no major damage to the body. The vent screen is in place and clear.

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Failure Analysis Regulator #13

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Figure 2: Regulator #13

The inside of the second-stage portion of this regulator was fairly clean, as shown in Figure 3. There was a

small amount of dirt and corrosion on the diaphragm plate and small amounts of debris on the upper surface of the

diaphragm. There was also some corrosion on the bottom of the adjustment spring plate as shown in Figure 4.

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Failure Analysis Regulator #13

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Figure 3: Top of Second-Stage Portion (Regulator #13)

Figure 4: Bottom of Adjustment Spring Plate (Regulator #13)

The diaphragm itself was in excellent condition. A few creases were observed on the top surface of the

diaphragm, most noticeably at 6 o’clock in Figure 5. However there was no evidence of cracking or fatigue due to

the creases. Some oily residue was observed on the lower surface of the diaphragm, most apparent where the

diaphragm contacts the body as shown in Figure 6. There was no evidence that the oil damaged the integrity or

functionality of the diaphragm. The sealing surfaces of the diaphragm, both with the body and the PRD, were clean

and in good condition.

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Failure Analysis Regulator #13

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Figure 5: Top of Second-Stage Diaphragm (Regulator #13)

Figure 6: Bottom of Second-Stage Diaphragm (Regulator #13)

The lower half of the body of the second-stage portion of the regulator was remarkably clean. There were a

few large chunks of some foreign material in the bottom half of the body. The largest of these is circled in Figure 7

and shown in more detail in Figure 8. The material was suspected to be remnants of pipe dope used during the

installation of the regulator. The coloring of the material was similar to that of the pipe dope found on the outlet

threads of the regulator. Additionally, like dried pipe dope, the chunks of material could be crushed to a fine powder

by applying sufficient force. It is worth noting that for the second-stage inlet to be fully closed, the PRD stem is

raised. For full-open, the PRD stem is lowered (and most likely to have its motion inhibited by the debris). So it is

possible the debris blocked the opening of the second-stage, resulting in a maximum flow of 65 scfm (Figure 1)

rather than the 80 scfm target.

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Failure Analysis Regulator #13

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Figure 7: Bottom Body of Second-Stage (Regulator #13)

Figure 8: Close-up of Debris in Bottom Body of Second-Stage (Regulator #13)

The inlet to the second-stage (outlet of the first-stage) is shown in Figure 9. There was a large amount of

dark particulate debris, as well as some small metal shavings. It is undeterminable if these were in the regulator

while assembled, or if they were deposited by debris from the disassembly. The screws holding together the two

halves of the first-stage were rusted in place and difficult to remove. (Note the screw that sheared during removal in

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Failure Analysis Regulator #13

Page C-7

the upper left corner of Figure 9). So the debris and metal shavings could have come from the corroded screws as

they were removed.

Due to the construction of the linkage assembly, it was impossible to remove the assembly and inspect the

seal on the rubber inlet. No major wear or cuts were observed by the limited inspection. As with the rest of the

body, a small amount of debris and metal shavings from an undeterminable source were found on the rubber.

Figure 9: Inlet to the Second-Stage (Outlet of the First-Stage) (Regulator #13)

The first-stage plate is shown in Figure 10. A small amount of debris was found on the rubber face. Given

it’s somewhat shielded location in the assembly, it is more probable (but cannot be guaranteed) that the debris had

been on the rubber face while the regulator was assembled. There was no debris, nor imprints of where debris had

been, on the seal line of the rubber.

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Failure Analysis Regulator #13

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Figure 10: First-Stage Plate (Regulator #13)

Figure 11: First-Stage Outlet (Regulator #13)

The first-stage diaphragm is shown in Figure 12. The diaphragm was less flexible than the second-stage

diaphragm. Clear indentations were left on the diaphragm on all sealing edges. A small tear in the diaphragm on

the inlet side was observed (at 3 o’clock in Figure 12). The tear did not extend through the sealing edge of the pass

through (Figure 11). The diaphragm appeared to be constructed of a woven layer sandwiched by rubber layers. The

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Failure Analysis Regulator #13

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tear extended through the depth of the rubber layer on the inlet side, but not through the woven layer or the other

rubber layer.

Figure 12: First-Stage Diaphragm (Regulator #13)

Summary

Dried remnants of pipe dope found in the second-stage body are likely to have prevented the full opening

of the second-stage inlet and therefore the subsequent failure of this regulator to allow a flow of 80 scfm.

The testing data indicates the high lock-up pressure is probably due to a small leak through the face seals

on the rubber surfaces of either the first or second stages (Figures 9 and 10). No conclusive evidence of debris

creating a leak path was found due to the limited accessibility of the second-stage surface and the amount of debris

generated during inspection that could have affected the first-stage and second-stage observations.

Two leak path hypotheses are proposed. Firstly, it is possible that some of the debris found during

inspection was indeed preventing proper sealing of the interface. Secondly, there is some variability in the

movement of the parts that create the seal during lock-up. Both rubber portions of the seals showed signs of

permanent deformation. Perhaps there was enough tolerance in the relative movement of the parts that allowed a

slight misalignment of the sealing interface over a permanently deformed ring, thereby creating a leak path.

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Failure Analysis Regulator #353

Page C-10

Problem

This second-stage regulator failed testing due to slow lockup and high lockup pressures. A

typical flow test plot is shown in Figure 1. At lockup the outlet pressure increases to a steady value

around 22 inH2O.

Regulator 42 Flow Test - 5 psig Inlet

9101112131415161718192021222324

51:00 52:00 53:00 54:00Time (mm:ss)

Out

let

Pre

ssur

e (i

nH2O

)

-100102030405060708090100110120130

Flo

w (s

cfm

)

Outlet Pressure Flow Flow

Figure 1: Regulator #42 Flow Test, Low Inlet Pressure

Inspection

The regulator body is in good condition, as shown in Figure 2.. There were small amounts of

dirt on the body and slight corrosion on or around the screws that hold the two halves of the body

together.

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Failure Analysis Regulator #353

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Figure 2: Regulator #42

A small piece of debris was observed on the inlet seat disc as shown in Figure 3. The piece of

debris was removed and measured to be approximately 1/8” x 1/16” x 1/32”. Based on the amount of

pipe dope on the regulator inlet (Figure 3) it is quite possible this piece of debris is simply a small

fragment of dried pipe dope that fell into the inlet after testing was completed, and therefore not the

root cause of the failure.

Figure 3: Debris Found on Inlet of Regulator #42

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Failure Analysis Regulator #353

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The upper half of the regulator body was removed and the diaphragm inspected. The

diaphragm was found in good condition. No tears, scratches, cracking, or other signs of damage were

obsevered. The adhesive bonding the diaphragm to the diaphragm plate was not very strong; it was

easy to separate the two parts. However, since the adhesive is not a pressure sealing interface, the

quality of the adhesive will not affect regulator performance.

Figure 4: Regulator #42 Diaphragm and Diaphragm Plate

The underside of the diaphragm was found to be in good condition, as shown in Figure 5.

The sealing interface between the PRD stem and the diaphragm was in excellent condition. A clear,

uniform mark of the interface was observed. There were no indications of any potential leak paths

through this seal.

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Failure Analysis Regulator #353

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Figure 5: Underside of Regulator #42 Diaphragm

The nozzle orifice piece was removed from the regulator inlet. Noticeable damage to the seat

disc was observed (Figure 6). Note that the regulator has been rotated relative to Figure 3.

Accounting for this rotation, the piece of debris observed there was found at approximately 2 o’clock

in Figure 6 and the damage shown is found at 10 o’clock. Due to the construction it was not possible

to easily remove the seat disc from the body. Therefore, it was difficult to examine the damage to the

seat disc in detail. The marks found on the seat disc appeared to indicate both compression of the

seat disc by a foreign body as well as a small amount of material removal from the seat disc.

The cause of the damage did not appear to be the nozzle orifice. It is shown in Figure 7. The

edge of the orifice is smooth and clean with no nicks or sharp edges that could cut the seat disc.

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Failure Analysis Regulator #353

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Figure 6: Damage to Inlet Seat Disc of Regulator #42

Figure 7: Nozzle Orifice of Regulator #42

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Failure Analysis Regulator #353

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Summary

Based on the results of the flow test (Figure 1) and the observed damage on the seat disc

(Figure 6), the following failure mechanism is proposed. Under lockup conditions, the damage to the

seat disc is a leak path from the inlet to the outlet. At a normal lockup pressure the leak path still is

open. As the outlet pressure increases (to approximately 22 inH2O) the additional pressure is

enough to seal the leak path and prevent further increase in the outlet pressure.

The cause of the leak path is undetermined. The piece of debris shown in Figure 3 is a

possibility. If this debris is in fact pipe dope, it is much more likely that it would disintegrate (and

not damage the seat disc) if it got trapped between the seat disc and the orifice. The bottom half of

the regulator body was remarkably clean; no significant amounts of grit or other foreign bodies were

found. The outlet opening on the body is relatively large, so it is quite possible that the foreign body

that caused the damage fell out of the regulator during transport.

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Failure Analysis Regulator #353

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Problem

This second-stage regulator “chatters & leaks thru PRD at 10 psig inlet and 30 cfh”. It was

removed from the field because the tank and regulator were removed from service.

Inspection

The outside of the regulator body is in good condition. There are no signs of damage or

abuse. The regulator functionality was tested before any disassembly or modifications were done.

Air was blown through the regulator at lung pressure. When the outlet was open, all the sensible

flow left the regulator through the outlet; no leakage through the PRD was found. If the outlet was

covered, a small amount of air leaked through the PRD. As the inlet pressure was increased, the

leak through the PRD stopped. Due to the small capacity of human lungs, it is possible that leakage

through the PRD occurred while the outlet was open. But since the volumetric flow was so low, no

discernible flow through the PRD could be observed.

In summary, at low inlet pressures the regulator leaked through the PRD. As the inlet

pressure increased, the leak sealed.

Figure 1: Regulator #72

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Failure Analysis Regulator #353

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During disassembly, the first step was to remove the setpoint spring. The spring was fully

compressed.

The diaphragm plate was removed and the upper surface of the diaphragm was inspected

(Figure 2). The diaphragm appeared in good condition. No tears, cuts, holes, or any other indication

of leakage was found. Small amounts of dirt and other debris were found on top of the diaphragm,

but no large or sharp pieces were noted.

Figure 2: Top of Diaphragm (Regulator #72)

The diaphragm was separated from the control linkage and the bottom was inspected. There

was a noticeable amount of rust or other debris in the bottom half of the regulator body and on the

bottom of the diaphragm (Figure 3). The suspected source is the bell-shaped portion of the control

linkage.

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Failure Analysis Regulator #353

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Figure 3: Bottom Half of Body (Regulator #72)

Near the central hole where the control linkage passes through the diaphragm two

observations were noted. Firstly a small, sharp-edged, translucent piece of debris was found. The

debris could have been glass, plastic, or another material. The debris was located on the sealing face

between the control linkage and the bottom of the diaphragm. Note its location in Figure 4.

Additionally, two distinct circles are observed where the seal between the diaphragm bottom and the

control linkage. Both of these circles coincide with the location of the translucent debris, indicating

that it was perhaps a pivot point for the shift.

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Failure Analysis Regulator #353

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Figure 4: Debris on Seal Between Diaphragm Bottom and Control Linkage

The piece of translucent debris was removed and saved. A distinct impression was left on

the diaphragm where the piece of debris was located (Figure 5).

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Failure Analysis Regulator #353

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Figure 5: Removed Debris on Seal Between Diaphragm Bottom and Control Linkage

Summary

Based on the observations and inspection notes, the failure mode of this regulator is a leak

from the inlet, past the piece of translucent debris, to the top half of the regulator body, and out the

PRD.

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Failure Analysis Regulator #353

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Problem

This single-stage regulator “chatters & leaks thru PRD at 100 psig inlet and 30 cfh”. It had

been removed from service since it reached the end of manufacturer’s service life.

Inspection

The assembled body of Regulator 353 was in good condition. There was a fair amount of dirt

and insect webs on the outside of the body. The vent screen was in place, and only some small debris

was found on the rubber diaphragm that covers the vent. Silver paint coated the body near the

regulator inlet, outlet, and vent. Additional silver paint can be seen on the outside edge of the two

halves of the body in Figure 1.

Figure 1: Regulator #353 (Cap Removed)

The body was opened and a visible area where some foreign substance had pooled in the body

was immediately evident. Figure 2 shows the upper and lower halves of the regulator body. A

distinct line across the diaphragm, diaphragm plate and body indicates where the pooling occurred.

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Failure Analysis Regulator #353

Page C-22

If the foreign substance entered the regulator body as a liquid, any moisture evaporated well before

this regulator was examined. A thin coating of white residue was left, as well as a significant build-

up of the substance at the bottom of the pool on the diaphragm plate. The build-up was a finely

compressed powder, not loose and dispersible. It was chalky in texture.

If this residue was indeed left by some pool of liquid that accumulated inside the regulator,

the angle of the pool is of interest. The parts shown in Figure 2 have not been rotated. Assuming

the pooling was due to gravity, the angle of installation was approximately 25° from horizontal (Inlet

at 10 o’clock and outlet at 4 o’clock). This is not in accordance with the manufacturers instructions

stamped on the body, specifying installation with the vent facing downward.

In addition to the residue from the pool or foreign substance, there was a substantial amount

of other debris, flakes, and particles on the inside of the regulator body.

Figure 2: Inside of Regulator #353 Body

The edge of the diaphragm plate where the pool of liquid had resided was slightly corroded,

as shown in Figure 3.

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Failure Analysis Regulator #353

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Figure 3: Corrosion and Residue on Plate (Regulator #353)

Upon removal of the diaphragm plate, a large amount of debris was found on top of the

diaphragm and on the pressure relief valve stem (Figure 4). The diaphragm itself appeared in good

condition. There was no evidence of cuts, tears, or any other damage due to the debris or rusted edge

of the diaphragm plate.

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Failure Analysis Regulator #353

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Figure 4: Debris on Diaphragm and PRD Stem (Regulator #353)

The bottom half of the regulator body was much cleaner, as shown in Figure 5. A few small

specks of the white debris/flakes were found, as was a small quantity of some black particulate near

the regulator outlet.

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Failure Analysis Regulator #353

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Figure 5: Bottom Half of Body (Regulator #353)

The bottom side of the diaphragm had a significant amount of debris on it, as shown in

Figure 6. For the most part, the debris on the bottom side of the regulator was much smaller in

particle size than that on top. There was a significant amount of debris on the sealing face between

the diaphragm and the PRD stem, as shown in Figure 7. This debris was more comparable in size to

the particles found on top of the diaphragm, and not on the bottom.

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Failure Analysis Regulator #353

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Figure 6: Bottom Side of Diaphragm (Regulator #353)

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Failure Analysis Regulator #353

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Figure 7: Debris on Sealing Surface Between Diaphragm and PRD Stem

Summary

No obvious causes of failures were found during inspection. A significant amount of debris,

including evidence of liquid pooling, was found on the top half of the regulator body.

The angle of pooling indicates that either the regulator was not installed in the correct orientation,

or that the liquid had accumulated inside the regulator before installation.

If the pooling occurred after installation, the angle indicates the vent was facing somewhat

downward, so the accumulation of rainwater inside the regulator is unlikely. The color of the liquid

residue (white) is inconsistent with the manufacturer’s paint (bronze) and the paint later applied

(silver).

Based upon the large amount of the unknown white debris on the top half of the diaphragm,

the PRD stem, and the sealing surface between the diaphragm bottom and PRD stem, the following

failure mechanism is proposed. A large amount of an undetermined liquid entered the top half of the

regulator body before or after installation. Upon evaporation of the liquid, a large amount of

particulate matter remained on the top half of the diaphragm and the exposed portion of the PRD

stem. The regulator experienced a true excess inlet pressure event, causing the diaphragm to

separate from the PRD to relive the excess pressure. While unseated, a significant quantity of the

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Failure Analysis Regulator #353

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debris entered the sealing face between the diaphragm and the PRD stem. The debris prevented a

proper resealing and the consequential leak through the PRD

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Failure Analysis Regulator #361

Page C-29

Problem

This first stage regulator failed due to a low relief start-to-discharge pressure and a low

reseating pressure. The S-T-D pressure was approximately 11 psig and the reseating pressure was

10.8 psig. A plot of two sequential relief tests is shown in Figure 1. During testing it was noted that

the adjustment spring was fully compressed and the maximum outlet pressure was about 10 psig.

Regulator 361 Relief Test

10.0

10.2

10.4

10.6

10.8

11.0

11.2

11.4

11.6

11.8

12.0

49:00 49:30 50:00 50:30 51:00 51:30 52:00 52:30Time

Rel

ief P

ress

ure

(psi

g)

0

10

20

30

40

50

60

70

80

90

100

Flo

w (c

fm)

Pressure Flow

Figure 1: Regulator #361 Relief Test

Inspection

Regulator #361 is shown below if Figure 1. An inspection of the assembled regulator found it

to be in acceptable condition. Paint had started to chip off the regulator body, but no damage to the

integrity of the body was found. There was some corrosion of the bolts holding the two halves of the

body together. Small amounts of dirt were found on the outside of the regulator body.

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Failure Analysis Regulator #361

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Figure 2: Regulator #361

The upper half of the regulator body was removed and the inside of the regulator was

inspected (Figure 3). A noticeable amount of dirt and debris were found on the upper surface of the

diaphragm and plate. The diaphragm itself appeared to be in good condition. The mark noticeable

at 12 o’clock is not indicative of any damage to the diaphragm integrity; it appears to be a stray spot

of adhesive used to bond the diaphragm to the plate. The PRD spring was found in good condition.

Figure 3: Diaphragm and Diphragm Plate of Regulator #361

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Failure Analysis Regulator #361

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It was noted that marks on the diaphragm plate indicate the set point spring was off center.

There are scratches on the raised lip of the plate at approximately 10 o’clock, as shown in Figure 4.

Given the freshness of the marks (bright silvery metal is exposed, rather than corrosion) it is likely

they were made during disassembly.

Figure 4: Scratches on Regulator #361 Diaphragm Plate

The diaphragm and plate assembly were removed and inspected. The top surface of the

diaphragm was in good condition. A large cut was observed on the bottom surface of the regulator.

This cut was at 3 o’clock in Figure 3 (very near the regulator outlet). The cut was approximately 3/8”

in length. The depth of the cut reached a woven layer within the diaphragm. It did not appear to

extend through the diaphragm to the upper side. An inspection of the top side of the diaphragm at

the location of the cut did not identify any evidence that the cut extended through the diaphragm.

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Failure Analysis Regulator #361

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Figure 5: Cut on Bottom of Regulator #361 Diaphragm

An inspection of the lower half of the regulator body did not find any potential causes for the

cut. The cut was located approximately above the regulator outlet. Figure 6 shows this portion of

the lower half of the regulator body. All edges were smooth and rounded. There were no sharp

edges or foreign bodies found that would have caused the cut.

With the exception of the cut, the rest of the diaphragm was in good condition. The seal

between the PRD stem and the diaphragm was distinct and uniform in quality, as shown in Figure

7. There were small particles of dirt or other debris, but there was no evidence that these had

interfered with the seal. A small nick was noted on the edge of the PRD stem (1 o’clock in Figure 7).

It was barely noticeable, and the uniform quality of the impression on the diaphragm indicates that

it didn’t affect the quality of the seal.

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Failure Analysis Regulator #361

Page C-33

Figure 6: Bottom Half of Regulator #361 Body

Figure 7: PRD Stem and Seal with Diaphragm

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Failure Analysis Regulator #361

Page C-34

Summary

No specific cause for the low S-T-D pressure was found. Bits of evidence lead to many

possible causes, but no single conclusive cause.

The scratches on the diaphragm plate indicate that the setpoint spring may have been

installed off center. If that was the case, it would exert an uneven force on the plate, and the

balancing force on the PRD stem seal would also be unbalanced. This could cause the PRD seal to

open at a lower pressure. However the lack of corrosion on those scratches indicates they were

probably made during the inspection, and not during the service life of the regulator.

The cut on the bottom of the regulator could also be a cause for the low S-T-D pressure.

Although no evidence that this cut extended through the entire diaphragm was found, it is possible a

small leak path opens at a pressure of 10 psig.

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Failure Analysis Regulator #383

Page C-35

Problem

This single-stage regulator was noted to have high lock-up pressure. A plot of a typical flow

test is shown in Figure 1.

Regulator383 Flow Test - 100 psig Inlet

5.07.5

10.012.515.017.520.022.525.027.530.032.535.037.540.0

43:15 43:30 43:45 44:00 44:15 44:30 44:45Time (mm:ss)

Out

let

Pre

ssur

e (i

nH2O

)

-100102030405060708090100110120130

Flo

w (s

cfm

)

Outlet Pressure Flow

Figure 1: Regulator #383 Flow Test (100 psig Inlet)

Inspection

The outer body of Regulator #383 was found in good condition, as shown in Figure 2. There

was some buildup of dirt on the body surfaces, but none appeared to interfere with the functionality

of the regulator.

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Failure Analysis Regulator #383

Page C-36

Figure 2: Regulator #383

The upper half of the body was removed and the diaphragm was inspected (Figure 3). The

inside of the regulator was very clean. The diaphragm was found to be in good condition, with no

cuts or scrapes. Yellow paint was noted on the diaphragm plate. This color and location matches the

color and location of paint on the set-point spring, indicating the spring was painted during

assembly. The diaphragm was thinner than typically noted during the regulator inspections.

The underside of the diaphragm was also found to be in good condition, as shown in Figure 4.

Slight discoloration of the diaphragm was noted. The irregular ring that appears darker (marked

with an arrow in Figure 4) corresponds exactly to the location of the adhesive bonding the diaphragm

to the plate. Beyond the discoloration, there was no indication that the adhesive damaged the

integrity of the diaphragm. Small amounts of fine grit were observed near the edge of the

diaphragm.

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Failure Analysis Regulator #383

Page C-37

Figure 3: Diaphragm and Plate of Regulator #383

Figure 4: Bottom of Regulator #383 Diaphragm

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Failure Analysis Regulator #383

Page C-38

The seal between the PRD stem and the diaphragm was in good condition, as shown in

Figure 5. Although there was small amounts of dirt and debris in the vicinity of the seal, there was

no indication that it prevented a proper seal from occurring.

Figure 5: PRD Seal on Bottom of Regulator #383 Diaphragm

The nozzle orifice was removed from the inlet of the regulator. Substantial degradation of

the seat disc was apparent, as shown in Figure 6. It appears the damage is a loss of material from

the seat disc (and not solely compression set). A significant amount of debris was found between the

orifice and seat disc. The debris was collected in a bag and is shown in Figure 7. It is suspected that

some of this debris is material lost from the seat disc.

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Failure Analysis Regulator #383

Page C-39

Figure 6: Inlet Seat Disc on Regulator #383

Figure 7: Dirt and Debris Removed Between Nozzle Orifice and Seat Disc

The nozzle orifice is shown in Figure 8. The edge of the orifice was smooth and had no sharp

edges. This indicates the damage to the seat disc was not caused by the orifice cutting the disc. A

dark substance was noted on the large face of the orifice. This may be the same substance that was

noted in substantial quantities on the inlet to the orifice (Figure 9). Although the exact rotational

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Failure Analysis Regulator #383

Page C-40

position of the orifice fitting during assembly is unknown, it is probable that the dark substance

gravimetrically settled out of the propane.

Figure 8: Nozzle Orifice of Regulator #383

Figure 9: Inlet Side of Nozzle Orifice of Regulator #383

Summary

Based on these observations, the following failure mechanism is proposed. Damage to the

seat disc prevents a proper seal between the inlet and outlet from being formed. Under lock-up

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Failure Analysis Regulator #383

Page C-41

conditions, leakage occurs until the outlet pressure is approximately 35 inH2O. At this pressure

enough force is generated to form the seal between the degraded seat disc and the inlet orifice. No

physical cause of the damage to the seat disc was found. The dark substance on the orifice fitting

may indicate the presence of an impurity in the propane that chemically attacked the seat disc.

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Failure Analysis Regulator #490

Page C-42

Problem

Regulator #490 is an integral two-stage regulator. It failed testing because it “chatters and

leaks thru PRV at 30 cfh”. It was removed from service because the installation was changed to a

dual stage system.

Inspection

The outside body of Regulator #490 is in good condition, as shown in Figure 1. There is

some corrosion on some of the screws holding together the body, but there is no indication that they

had corroded to failure or that the body was corroded.

Figure 1: Regulator #490

A significant amount of dirt and debris was seen in the second-stage vent. Figure 2 shows

the vent from both the outside and inside of the body. The vent screen was in place when the

regulator was arrived; it was removed before the pictures of Figure 2 were taken. The outstanding

condition of the inside of the body indicates that while there may have been noticeable corrosion or

debris on the vent outlet, the vent valve was effective in preventing the majority of it from entering

the regulator body.

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Failure Analysis Regulator #490

Page C-43

Figure 2: Second-Stage Vent (Regulator #490)

The top half of the second-stage of the regulator was in good condition as well (Figure 3).

The PRD spring and adjustment spring were in good condition. There was relatively little debris

contained within the regulator. No damage to the diaphragm or diaphragm plate was noticed. The

diaphragm itself was adhesively bonded to the diaphragm plate. This bond appeared in good

condition with no large, detectable failures.

Figure 3: Top Half of Second-Stage (Regulator #490)

The bottom of the diaphragm was in similarly good condition. Two marks where the

diaphragm contacted the lower body are visible at 2 o’clock and 8 o’clock in Figure 4. These marks

did not cut or damage the diaphragm. The contacting surface between the diaphragm and the PRD

stem was in good condition.

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Failure Analysis Regulator #490

Page C-44

Figure 4: Bottom of Second-Stage Diaphragm (Regulator #490)

The white plastic PRD stem, as well as a portion of the lower half of the second-stage body, is

shown in Figure 5. The PRD stem was in good condition. No cracks or chips were observed. The

outside edge that creates the seal with the second-stage diaphragm was slightly discolored, but

otherwise in good condition.

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Failure Analysis Regulator #490

Page C-45

Figure 5: PRD Stem and Bottom of Second-Stage Body (Regulator #490)

The PRD stem was removed and the linkage assembly between the first and second stages

was examined. The assembly is shown in Figure 6. The assembly appeared to be in good working

order. No debris was found that would prevent proper operation of the linkage. The O-ring

appeared in good condition, with no evidence of cracking or cuts.

There have been no apparent leak path from the second-stage inlet to the second-stage

outlet.

Figure 6: Second-Stage Linkage Assembly (Regulator #490)

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Failure Analysis Regulator #490

Page C-46

The first-stage portion of the regulator was more difficult to disassemble due to the use of

rivets in the construction. The limited disassembly found little evidence of failure. Figure 7 shows

the first-stage portion of this regulator. There is some paint on the outer edges of the diaphragm,

but none appears to extend into the working seals of the regulator. No significant dirt or debris was

found in this portion of the regulator. The diaphragm itself was in good condition; No cracks or cuts

were observed. It was impossible to non-destructively disassemble the outlet side of the first-stage of

the regulator to examine the sealing surface of the rubber cap.

Figure 7: First-Stage Portion of Regulator #490

Figure 8 shows the inlet side of the first-stage portion of this regulator. The spring was in

good condition. No dirt or debris was found in this side of the regulator either. The bond between

the diaphragm and the plate was in good condition with no noticeable gaps or leak paths.

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Failure Analysis Regulator #490

Page C-47

Figure 8: Inlet Side of First-Stage Portion of Regulator #490

The O-ring seal on the shaft pass-through from the inlet to the outlet was in good condition.

Note that the O-ring shown in Figure 9 has been pushed up during the examination. No leak path

was observed around the O-ring. Note that the plate and threads of the shaft show signs of some

scale buildup. The scale buildup was generally small in nature, and no significant amounts of loose

scale or debris were observed.

Figure 9: First-Stage Diphragm (Regulator #490)

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Failure Analysis Regulator #490

Page C-48

Summary

No failure mode was found for this regulator. The inside of the regulator body was generally

clean. All observable seals were in good condition. There was nothing observed that would block or

impair the normal motion of either the first or the second-stage linkages.

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Failure Analysis Regulator #538

Page C-49

Problem

This first stage regulator “leaks thru PRD at 25 psig inlet and 0 cfh; high lock-up”. It was

removed from service because the tank and regulator were both removed from the service at location.

Inspection

The outside of the regulator body is in good shape. There are some small bits of dirt and

spiderweb on the relief screen, but not enough to cause any significant blockage.

Figure 1: Regulator #538

Upon disassembly possible leak paths between the high pressure inlet and the pressure relief

opening were identified. The two general areas are the diaphragm assembly and by the O-ring seal

on the shaft.

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Failure Analysis Regulator #538

Page C-50

Figure 2: Two halves of the body of #538 showing the two general leak interfaces, main

diaphragm (left) and O-ring seal on shaft (right)

A detailed visual inspection of the diaphragm (Figure 3) did not identify any potential leak

paths. The diaphragm appeared in good shape; there were no cuts, holes, scratches, cracks, or any

other evidence of failure. Permanent deformation at the sealing edges did not indicate any leak

paths. The ridge on the outside of the diameter was discernible for the entire circumference. The

height of the ridge was non-uniform along the circumference. One side in particular was somewhat

lower than the rest. However, this is not suspected to be a problem because a leak on the outside

circumference of the diaphragm would manifest itself as a body-leak and not the observed PRD leak.

Furthermore, even though the height was not as great, the ridge was still there, indicating that the

two halves of the body were tightened together adequately. The other sealing edge of the diaphragm

is on the inside circumference where the shaft passes through. A leak through this interface would

result in a leak through the PRD. However, the interface appeared good. There was a uniform ridge

inside the edge of the interface between shaft and the diaphragm indicating adequate tightening of

the joint. There was no debris, cuts, scrapes, tears, or any other indication that the seal between the

shaft and the diaphragm was faulty.

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Failure Analysis Regulator #538

Page C-51

Figure 3: Main Diaphragm of #538. Note the Zig-Zag marks on the surface were put there

during disassembly of the diaphragm/shaft.

A detailed inspection of the shaft (Figure 4) identified a potential leak path to the PRD. During

manufacture the shaft was turned to a smooth finish, as indicated by the pattern of small

circumferential lines. There was a large diagonal scrape along the shaft, as show in Figure 4. The

shaft is discolored at the very end (just right of the circle marking the diagonal scrape) where it

extended beyond the O-ring seal interface and into the propane flow. A circumferential mark

through the middle of the diagonal scrape is the normal operating location of the O-ring. Although

the diagonal scrape does not appear very deep, this is the most probable observed leak path to the

PRD opening. The O-ring was not removed for inspection since the removal would likely damage the

O-ring, making it impossible to distinguish between a previous failure and the current destructive

process.

Ridge at body/diaphragm seal Ridge at shaft/diaphragm seal

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Failure Analysis Regulator #538

Page C-52

Figure 4: Shaft of Regulator #538

Summary

Based on the observations, the most probable leak path is past the O-ring, through the

diagonal scratch on the shaft.

Normal O-ring Location

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Failure Analysis Regulator #571

Page C-53

Problem

This first-stage regulator “leaked through PRD during adjustment”.

Inspection

Regulator 571 is shown below in Figure 1. This regulator arrived painted fully painted. The

paint was removed from the top half of the body in order to locate the manufacture date stamp on

the regulator.

Figure 1: Regulator #571

The top half of the body was removed and the inside examined. The upper half of the

regulator appeared to be in good condition. It was relatively clean and showed no signs of damage.

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Failure Analysis Regulator #571

Page C-54

Figure 2: Regulator #571 with Top of Body Removed

The diaphragm and PRD spring were removed and the bottom half of the regulator body was

inspected. There was a significant amount of grit, paint particles, and other debris in the bottom of

the regulator. Included in the debris were two large metal shavings. The debris (including the

metal shavings) are shown in Figure 3. It is possible that the metal shavings were located below the

linkage in the bottom of the regulator body, inhibiting the full range of movement and preventing the

inlet from closing.

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Failure Analysis Regulator #571

Page C-55

Figure 3: Particles and Shavings (circled) Found inside Bottom of Regulator #571

The diaphragm was removed and inspected. Overall the diaphragm was in good condition,

with no cuts, scrapes, cracks, or other signs of damage. The diaphragm plate was bonded to the

diaphragm. The bond appeared to be in good condition with no noticeable gaps in its coverage. The

seal with the PRD stem on the underside of the diaphragm was in good condition. There was no

debris or evidence of a leak path through the sealing interface.

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Failure Analysis Regulator #571

Page C-56

Figure 4: Bottom of Diaphragm (Regulator #571)

The control linkage was removed and inspected. The plastic parts of the linkage assembly

were in good condition. No chips, breaks, or fractures were observed. There was some white powder

observed on the sides of the PRD stem, indicating slight wear. The O-ring on the linkage assembly

had a dried white residue on its surface. This did not seem to affect the quality of the O-ring; the

outer surface was smooth with no cracks, scrapes, or signs of degradation.

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Failure Analysis Regulator #571

Page C-57

Figure 5: Control Linkage Assembly (Regulator #571)

The seat disc from the control linkage assembly was examined. There was a hard edge on

one side of the seat impression. Additionally there was a fair amount of grit covering the entire face

of the rubber seal.

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Failure Analysis Regulator #571

Page C-58

Figure 6: Seat Disc from Control Linkage (Regulator #571)

Summary

Based on the inspection, the most probable explanation for leakage through the PRD was

the presence of metal shavings in the lower half of the body. The metal shavings prevented the

control linkage assembly from fully closing the inlet to the regulator, thereby allowing excess

pressure to build up within the regulator body.

Alternatively, it could have been the grit on the seat disc that caused the PRD to discharge

under normal operating conditions. The grit could have prevented the inlet from being completely

sealed when the desired regulated pressure was realized.

The sealing interfaces between the control linkage and diaphragm (PRD stem seal) and

between the control linkage and body (O-ring) were in good condition and there was no indication

that these were leak paths from the inlet.

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Failure Analysis Regulator #711

Page C-59

Problem

This second-stage regulator did not relieve during the relief test.

Inspection

Regulator 711 is shown in Figure 1. In this picture, it is apparent there are substantial

amounts of spider webs in the vent.

Figure 1: Regulator #711

Figure 2 is a close up of the vent, taken before any cleaning or inspection. It is apparent that

the vent screen is not in place, allowing for the spider webs to freely enter the inside of the regulator

body.

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Failure Analysis Regulator #711

Page C-60

Figure 2: Regulator #711 Vent

The spider webs were removed from the vent. The vent passage (approximately 1/8” in

diameter) was completely plugged by dirt and old spider webs. Figure 3 shows the vent after the

spider webs were removed and the vent path cleared.

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Failure Analysis Regulator #711

Page C-61

Figure 3: Regulator #711 Vent (After Cleaning)

Several dead insects were found inside the regulator body, as shown in Figure 4. The

diaphragm plate, PRD spring, and associated assembly were in good condition. There was no

indication that the PRD itself failed to actuate.

\

Figure 4: Inside Body of Regulator #711

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Failure Analysis Regulator #711

Page C-62

Summary

It has been determined that this regulator failed the relief test since the vent passage was

blocked by mud. There was no indication that the PRD itself failed to actuate to excess pressure.